Ch01 Advanced Database mgmt Iyad Zaarour

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Advanced DataBase Management System

Lebanese University

Ali [email protected]

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Chapter 1. SQL : Structured Query Language

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Creating Tables: Syntax

You must have specific privileges:CREATE TABLEA storage area

CREATE TABLE CREATE TABLE table_nametable_name

((column datatypecolumn datatype [DEFAULT [DEFAULT exprexpr]]

[[column_constraintcolumn_constraint], ],

......

[[table_constrainttable_constraint]);]);

CREATE TABLE CREATE TABLE table_nametable_name

((column datatypecolumn datatype [DEFAULT [DEFAULT exprexpr]]

[[column_constraintcolumn_constraint], ],

......

[[table_constrainttable_constraint]);]);

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Naming Rules

Must begin with a letter

Can be 1–30 characters long

Must contain only A–Z, a–z, 0–9, _, $, and #

Must not duplicate the name of another object owned by the same user

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Datatypes

DatatypeDatatype

VARCHAR2(VARCHAR2(sizesize))

CHAR(CHAR(sizesize))

NUMBERNUMBER

NUMBER(NUMBER(pp,,ss))

DATEDATE

LONGLONG

CharChar

NUMBER (NUMBER (pp))

DescriptionDescription

Variable length character valuesVariable length character values

Fixed length character valuesFixed length character values

Floating point numbersFloating point numbers

Number values, p digits in which s are Number values, p digits in which s are

after the pointafter the point

Date and time valuesDate and time values

Variable length character values up to Variable length character values up to

2 GB2 GB

Single characterSingle character

Integer Number of p digits at maxInteger Number of p digits at max

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Constraint: Syntax

Column-constraint level

Table-constraint level

columncolumn [CONSTRAINT [CONSTRAINT constraint_nameconstraint_name] ] constraint_typeconstraint_type,,columncolumn [CONSTRAINT [CONSTRAINT constraint_nameconstraint_name] ] constraint_typeconstraint_type,,

column,...column,...

[CONSTRAINT constraint_name] constraint_type[CONSTRAINT constraint_name] constraint_type

(column, ...),(column, ...),

column,...column,...

[CONSTRAINT constraint_name] constraint_type[CONSTRAINT constraint_name] constraint_type

(column, ...),(column, ...),

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The NOT NULL Constraint

Ensures that null values are not permitted for the columnIs defined at the column-constraint level

Example

CREATE TABLECREATE TABLE friend...friend...

phonephone VARCHAR2(15) NOT NULL,...VARCHAR2(15) NOT NULL,...

last_namelast_name VARCHAR2(25) VARCHAR2(25)

CONSTRAINT friend_last_name_nn NOT NULL,...CONSTRAINT friend_last_name_nn NOT NULL,...

CREATE TABLECREATE TABLE friend...friend...

phonephone VARCHAR2(15) NOT NULL,...VARCHAR2(15) NOT NULL,...

last_namelast_name VARCHAR2(25) VARCHAR2(25)

CONSTRAINT friend_last_name_nn NOT NULL,...CONSTRAINT friend_last_name_nn NOT NULL,...

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The UNIQUE Constraint

Designates a column or combination of columns so that no two rows in the table can have the same value for this keyAllows null values if the UNIQUE key is based on a single columnIs defined at either the table or column-constraint levelAutomatically creates a UNIQUE index

... phone... phone VARCHAR2(10)VARCHAR2(10)

CONSTRAINT s_emp_phone_uk UNIQUE,...CONSTRAINT s_emp_phone_uk UNIQUE,...

... phone... phone VARCHAR2(10)VARCHAR2(10)

CONSTRAINT s_emp_phone_uk UNIQUE,...CONSTRAINT s_emp_phone_uk UNIQUE,...

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The PRIMARY KEY Constraint

Creates a primary key for the table; only one primary key is allowed for each tableEnforces uniqueness of columnsDoes not allow null values in any part of the primary keyIs defined at either the table or column constraint levelAutomatically creates a UNIQUE index

... id... id NUMBER(7)NUMBER(7)

CONSTRAINT s_emp_id_pk PRIMARY KEY,...CONSTRAINT s_emp_id_pk PRIMARY KEY,...

... id... id NUMBER(7)NUMBER(7)

CONSTRAINT s_emp_id_pk PRIMARY KEY,...CONSTRAINT s_emp_id_pk PRIMARY KEY,...

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The PRIMARY KEY Constraint

CREATE TABLE Sells (bar CHAR(20),goods VARCHAR2(20) DEFAULT ‘HouseBeer’,price REAL NOT NULL,

PRIMARY KEY (bar,goods) );

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The FOREIGN KEY Constraint

Designates a column or combination of columns as a foreign keyEstablishes a relationship between the primary or unique key in the same table or between tablesIs defined at either the table or column constraint levelMust match an existing value in the parent table or be NULL

... dept_id... dept_id NUMBER(7)NUMBER(7)

CONSTRAINT s_emp_dept_id_fk CONSTRAINT s_emp_dept_id_fk

REFERENCES s_dept(id),...REFERENCES s_dept(id),...

... dept_id... dept_id NUMBER(7)NUMBER(7)

CONSTRAINT s_emp_dept_id_fk CONSTRAINT s_emp_dept_id_fk

REFERENCES s_dept(id),...REFERENCES s_dept(id),...

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FOREIGN KEY Constraint Keywords

FOREIGN KEYDefines the column in the child table at the table constraint level

REFERENCESIdentifies the table and column in the parent table

ON DELETE CASCADEAllows deletion in the parent table and deletion of the dependent rows in the child table

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Foreign Key Violations

Two kinds of violating:1. Insert or update a tuple so it refers to a

nonexistent reference.Always rejected.

2. Delete or update a tuple that has a value some tuples refer to. Three choices:

a) Reject: This is the default.b) Cascade: Ripple changes to referring tuple.c) Set Null: Change referring tuples to have NULL

in referring components.

Oracle allows ‘ON DELETE CASCADE or ON DELETE SET NULL’ options. But, ‘ON UPDATE’ options are not allowed.

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Selecting a Policy

ON [DELETE, UPDATE] [CASCADE, SET NULL].

Example

CREATE TABLE Sells (bar CHAR(20),beer CHAR(20),price REAL,FOREIGN KEY beer REFERENCES Beers(name)

ON DELETE SET NULLON DELETE CASCADE);

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Attribute-Based Checks

Follow an attribute by a condition that must hold for that attribute in each tuple of its relation.

Syntax: CHECK <condition>.Condition may involve the checked attribute.

Condition is checked only when the associated attribute changes (i.e., an insert or update occurs).

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Attribute based Check: Example

CREATE TABLE Sells (bar CHAR(20),goods CHAR(20) ,price REAL CHECK (price <= 5.00)

);

Check occurs only when a ‘Sells’ tuple inserted or updated.

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Tuple-Based Checks

Separate element of table declaration.Syntax: similar to attribute-based check.

Checked whenever a tuple is inserted or updated.

Example Only Joe's Bar can sell goods for more than $5.

CREATE TABLE Sells (bar CHAR(20),goods CHAR(20),price REAL,CONSTRAINT joe_bar CHECK (bar = 'Joe''s Bar' OR

price <= 5.00));

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Create Table: Example

SQL> CREATE TABLE s_deptSQL> CREATE TABLE s_dept

2 (id 2 (id NUMBER(7)NUMBER(7)

3 CONSTRAINT s_dept_id_pk PRIMARY KEY, 3 CONSTRAINT s_dept_id_pk PRIMARY KEY,

4 name 4 name VARCHAR2(25)VARCHAR2(25)

5 CONSTRAINT s_dept_name_nn NOT NULL, 5 CONSTRAINT s_dept_name_nn NOT NULL,

6 region_id 6 region_id NUMBER(7)NUMBER(7)

7 CONSTRAINT s_dept_region_id_fk REFERENCES 7 CONSTRAINT s_dept_region_id_fk REFERENCES

8 s_region (id), 8 s_region (id),

9 CONSTRAINT s_dept_name_region_id_uk UNIQUE 9 CONSTRAINT s_dept_name_region_id_uk UNIQUE

10 (name, region_id)); 10 (name, region_id));

SQL> CREATE TABLE s_deptSQL> CREATE TABLE s_dept


3 CONSTRAINT s_dept_id_pk PRIMARY KEY, 3 CONSTRAINT s_dept_id_pk PRIMARY KEY,

4 name 4 name VARCHAR2(25)VARCHAR2(25)

5 CONSTRAINT s_dept_name_nn NOT NULL, 5 CONSTRAINT s_dept_name_nn NOT NULL,

6 region_id 6 region_id NUMBER(7)NUMBER(7)

7 CONSTRAINT s_dept_region_id_fk REFERENCES 7 CONSTRAINT s_dept_region_id_fk REFERENCES

8 s_region (id), 8 s_region (id),

9 CONSTRAINT s_dept_name_region_id_uk UNIQUE 9 CONSTRAINT s_dept_name_region_id_uk UNIQUE

10 (name, region_id)); 10 (name, region_id));

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Create Table: Example

SQL> CREATE TABLE s_empSQL> CREATE TABLE s_emp


3 CONSTRAINT s_emp_id_pk PRIMARY KEY, 3 CONSTRAINT s_emp_id_pk PRIMARY KEY,

4 last_name 4 last_name VARCHAR2(25)VARCHAR2(25)

5 CONSTRAINT s_emp_last_name_nn NOT NULL, 5 CONSTRAINT s_emp_last_name_nn NOT NULL,

6 first_name6 first_name VARCHAR2(25),VARCHAR2(25),

7 userid 7 userid VARCHAR2(8)VARCHAR2(8)

8 CONSTRAINT s_emp_userid_nn NOT NULL 8 CONSTRAINT s_emp_userid_nn NOT NULL

9 CONSTRAINT s_emp_userid_uk UNIQUE, 9 CONSTRAINT s_emp_userid_uk UNIQUE,

10 start_date 10 start_date DATE DEFAULT SYSDATE,DATE DEFAULT SYSDATE,

11 manager_id 11 manager_id NUMBER(7),NUMBER(7),

12 dept_id 12 dept_id NUMBER(7)NUMBER(7)

13 CONSTRAINT s_emp_dept_id_fk REFERENCES 13 CONSTRAINT s_emp_dept_id_fk REFERENCES

14 s_dept (id), 14 s_dept (id),

15 commission_pct 15 commission_pct NUMBER(4,2)NUMBER(4,2)

16 CONSTRAINT s_emp_commission_pct_ck CHECK 16 CONSTRAINT s_emp_commission_pct_ck CHECK

17 (commission_pct IN(10,12.5,15,17.5,20))); 17 (commission_pct IN(10,12.5,15,17.5,20)));

SQL> CREATE TABLE s_empSQL> CREATE TABLE s_emp


3 CONSTRAINT s_emp_id_pk PRIMARY KEY, 3 CONSTRAINT s_emp_id_pk PRIMARY KEY,

4 last_name 4 last_name VARCHAR2(25)VARCHAR2(25)

5 CONSTRAINT s_emp_last_name_nn NOT NULL, 5 CONSTRAINT s_emp_last_name_nn NOT NULL,

6 first_name6 first_name VARCHAR2(25),VARCHAR2(25),

7 userid 7 userid VARCHAR2(8)VARCHAR2(8)

8 CONSTRAINT s_emp_userid_nn NOT NULL 8 CONSTRAINT s_emp_userid_nn NOT NULL

9 CONSTRAINT s_emp_userid_uk UNIQUE, 9 CONSTRAINT s_emp_userid_uk UNIQUE,

10 start_date 10 start_date DATE DEFAULT SYSDATE,DATE DEFAULT SYSDATE,

11 manager_id 11 manager_id NUMBER(7),NUMBER(7),

12 dept_id 12 dept_id NUMBER(7)NUMBER(7)

13 CONSTRAINT s_emp_dept_id_fk REFERENCES 13 CONSTRAINT s_emp_dept_id_fk REFERENCES

14 s_dept (id), 14 s_dept (id),

15 commission_pct 15 commission_pct NUMBER(4,2)NUMBER(4,2)

16 CONSTRAINT s_emp_commission_pct_ck CHECK 16 CONSTRAINT s_emp_commission_pct_ck CHECK

17 (commission_pct IN(10,12.5,15,17.5,20))); 17 (commission_pct IN(10,12.5,15,17.5,20)));

Creating a Table by Using a SubQuery

Create a table and insert rows by combining the CREATE TABLE statement and AS subquery option.

Match the number of specified columns to the number of subquery columns.

Define columns with column names anddefault values.

CREATE TABLE tableCREATE TABLE table

[([(column, columncolumn, column...)]...)]

AS subquery;AS subquery;

CREATE TABLE tableCREATE TABLE table

[([(column, columncolumn, column...)]...)]

AS subquery;AS subquery;

Name Null? Type ---------------------------- -------- ----- EMPNO NOT NULL NUMBER(4) ENAME VARCHAR2(10) ANNSAL NUMBER HIREDATE DATE

Name Null? Type ---------------------------- -------- ----- EMPNO NOT NULL NUMBER(4) ENAME VARCHAR2(10) ANNSAL NUMBER HIREDATE DATE

SQL> DESCRIBE dept30SQL> DESCRIBE dept30SQL> DESCRIBE dept30SQL> DESCRIBE dept30

SQL> CREATE TABLE SQL> CREATE TABLE dept30dept30

22 AS AS

33 SELECTSELECT empno, ename, sal empno, ename, sal**12 AS ANNSAL, 12 AS ANNSAL,

hiredatehiredate

44 FROMFROM emp emp

55 WHEREWHERE deptno deptno = = 30;30;

Table createdTable created..

SQL> CREATE TABLE SQL> CREATE TABLE dept30dept30

22 AS AS

33 SELECTSELECT empno, ename, sal empno, ename, sal**12 AS ANNSAL, 12 AS ANNSAL,

hiredatehiredate

44 FROMFROM emp emp

55 WHEREWHERE deptno deptno = = 30;30;

Table createdTable created..

Creating a Table by using a Subquery

ALTER TABLE tableALTER TABLE table

ADDADD ( (column datatype column datatype [[DEFAULT exprDEFAULT expr]]

[[, column datatype, column datatype]...)]...);;


ADDADD ( (column datatype column datatype [[DEFAULT exprDEFAULT expr]]



MODIFYMODIFY ( (column datatype column datatype [[DEFAULT exprDEFAULT expr]]



MODIFYMODIFY ( (column datatype column datatype [[DEFAULT exprDEFAULT expr]]


Use the ALTER TABLE statement to:Add a new columnModify an existing columnDefine a default value for the new columnDrop a Column

The ALTER TABLE Statement

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Altering Tables

Add a new column.Define a default value for the new column.Specify that the column must contain a value.

ALTER TABLE ALTER TABLE tabletable

ADDADD ((column datatype column datatype [DEFAULT [DEFAULT exprexpr][NOT NULL]][NOT NULL]

[, [, column datatypecolumn datatype]...);]...);

ALTER TABLE ALTER TABLE tabletable

ADDADD ((column datatype column datatype [DEFAULT [DEFAULT exprexpr][NOT NULL]][NOT NULL]


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Adding a Column: Example

Add a COMMENTS column to the S_REGION table.

The new column becomes the last column.

SQL> ALTER TABLESQL> ALTER TABLE s_regions_region

2 ADD2 ADD (comments VARCHAR2(255));(comments VARCHAR2(255));

Table altered.Table altered.

SQL> ALTER TABLESQL> ALTER TABLE s_regions_region

2 ADD2 ADD (comments VARCHAR2(255));(comments VARCHAR2(255));


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Modifying a Column: Syntax

Change a column's datatype, size, default value, and NOT NULL column constraint.

ALTER TABLEALTER TABLE tabletableMODIFYMODIFY ((column datatype column datatype [DEFAULT [DEFAULT exprexpr][NOT NULL]][NOT NULL]


ALTER TABLEALTER TABLE tabletableMODIFYMODIFY ((column datatype column datatype [DEFAULT [DEFAULT exprexpr][NOT NULL]][NOT NULL]


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Modifying a Column

Change the data type if the column contains null values.Change the default value to affect only subsequent insertions into the table.

ExampleExtend the maximum length of the TITLE column in the S_EMP table to 50 characters.

SQL> ALTER TABLESQL> ALTER TABLE s_emps_emp

2 MODIFY 2 MODIFY (title VARCHAR2(50));(title VARCHAR2(50));



2 MODIFY 2 MODIFY (title VARCHAR2(50));(title VARCHAR2(50));


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Adding a Constraint: Example

Add a foreign key constraint to the S_EMP table indicating that a manager must already exist as a valid employee in the S_EMP table.


ADD CONSTRAINTADD CONSTRAINT s_emp_manager_id_fks_emp_manager_id_fk

FOREIGN KEY (manager_id)FOREIGN KEY (manager_id)

REFERENCES REFERENCES s_emp(id);s_emp(id);



ADD CONSTRAINTADD CONSTRAINT s_emp_manager_id_fks_emp_manager_id_fk

FOREIGN KEY (manager_id)FOREIGN KEY (manager_id)

REFERENCES REFERENCES s_emp(id);s_emp(id);


SQL> DROP TABLE dept30;SQL> DROP TABLE dept30;

Table droppedTable dropped..

SQL> DROP TABLE dept30;SQL> DROP TABLE dept30;

Table droppedTable dropped..

Dropping a Table

All data and structure in the table is deleted.Any pending transactions are committed.

All indexes are dropped.You cannot roll back this statement.

SQL> RENAME dept TO department;SQL> RENAME dept TO department;

Table renamedTable renamed..

SQL> RENAME dept TO department;SQL> RENAME dept TO department;

Table renamedTable renamed..

Changing the Name of an Object

To change the name of a table, view, sequence…

Execute the RENAME statement

You must be the owner of the object

SQL> TRUNCATE TABLE department;SQL> TRUNCATE TABLE department;

Table truncatedTable truncated..

SQL> TRUNCATE TABLE department;SQL> TRUNCATE TABLE department;

Table truncatedTable truncated..

Truncating a Table

The TRUNCATE TABLE Statement:Removes all rows from a tableReleases the storage space used by that table

You cannot roll back row removal when using TRUNCATE.

Alternatively, you can remove rows by using the DELETE statement.

You can add comments to a table or column by using the COMMENT statement.

Comments can be viewed through the data dictionary views.ALL_TAB_COMMENTSUSER_TAB_COMMENTS

Adding Comments to a Table

SQL> COMMENT ON TABLE emp SQL> COMMENT ON TABLE emp

2 IS 'Employee Information';2 IS 'Employee Information';

Comment createdComment created..

SQL> COMMENT ON TABLE emp SQL> COMMENT ON TABLE emp

2 IS 'Employee Information';2 IS 'Employee Information';

Comment createdComment created..

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Inserting Rows into a Table: Syntax

Add new rows to a table by using the INSERT command.

Only one row is inserted at a time with this syntax.

INSERT INTOINSERT INTO tabletable [( [(columncolumn [, [, columncolumn...])]...])]

VALUESVALUES ((valuevalue [, [, valuevalue...]);...]);

INSERT INTOINSERT INTO tabletable [( [(columncolumn [, [, columncolumn...])]...])]

VALUESVALUES ((valuevalue [, [, valuevalue...]);...]);

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Inserting Rows: Example

Insert a new row containing values for each column.Optionally list the columns in the INSERT clause.

List values in the default order of the columns in the table.

Enclose character and date values within single quotation marks.

SQL> INSERT INTOSQL> INSERT INTO s_depts_dept

2 VALUES2 VALUES (11, 'Finance', 2);(11, 'Finance', 2);

1 row created.1 row created.

SQL> INSERT INTOSQL> INSERT INTO s_depts_dept

2 VALUES2 VALUES (11, 'Finance', 2);(11, 'Finance', 2);

1 row created.1 row created.

SQL> INSERT INTO managersSQL> INSERT INTO managers((id, name, salary, hiredateid, name, salary, hiredate))

22 SELECTSELECT empno, ename, sal, hiredateempno, ename, sal, hiredate

33 FROM empFROM emp

44 WHEREWHERE job job = = 'MANAGER';'MANAGER';

3 rows created3 rows created..

SQL> INSERT INTO managersSQL> INSERT INTO managers((id, name, salary, hiredateid, name, salary, hiredate))

22 SELECTSELECT empno, ename, sal, hiredateempno, ename, sal, hiredate

33 FROM empFROM emp

44 WHEREWHERE job job = = 'MANAGER';'MANAGER';

3 rows created3 rows created..

Write your INSERT statement with a subquery.

Do not use the VALUES clause.Match the number of columns in the INSERT clause to those in the subquery.

Copying Rows from another Table

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Sequential lists of numbers to create unique surrogate key values

To use a sequence:SELECT sequence_name.NEXTVAL FROM DUAL;

INSERT INTO location (LOC_ID) VALUES(loc_id_sequence.NEXTVAL);

Loc_id_sequence.currval: Current Value

Sequences

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The Basic Query Block

SELECT identifies what columns

FROM identifies which table

SELECTSELECT [DISTINCT][DISTINCT] {*,column [alias],....}{*,column [alias],....}

FROMFROM table;table;

SELECTSELECT [DISTINCT][DISTINCT] {*,column [alias],....}{*,column [alias],....}

FROMFROM table;table;

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Selecting All Columns, All Rows

Simplest SELECT statement contains the followingtwo clauses:

SELECT clauseAsterisk (*) indicates all columns

FROM clause

SQL> SELECT SQL> SELECT ** 2 FROM 2 FROM s_dept;s_dept;


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Selecting All Columns, All Rows



IDID NAMENAME REGION_IDREGION_ID---------------- -------------------------- --------------------

1010 FinanceFinance 113131 SalesSales 113232 SalesSales 223333 SalesSales 333434 SalesSales 443535 SalesSales 554141 OperationsOperations 114242 OperationsOperations 224343 OperationsOperations 334444 OperationsOperations 444545 OperationsOperations 555050 AdministrationAdministration 11

12 rows selected.12 rows selected.

IDID NAMENAME REGION_IDREGION_ID---------------- -------------------------- --------------------

1010 FinanceFinance 113131 SalesSales 113232 SalesSales 223333 SalesSales 333434 SalesSales 443535 SalesSales 554141 OperationsOperations 114242 OperationsOperations 224343 OperationsOperations 334444 OperationsOperations 444545 OperationsOperations 555050 AdministrationAdministration 11

12 rows selected.12 rows selected.

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Selecting Specific Columns

List the columns in the SELECT clause.Separate columns by using a comma.Specify columns in the order you want them to appear.

SQL> SELECTSQL> SELECT dept_id, last_name, manager_iddept_id, last_name, manager_id 2 FROM2 FROM s_emp;s_emp;

SQL> SELECTSQL> SELECT dept_id, last_name, manager_iddept_id, last_name, manager_id 2 FROM2 FROM s_emp;s_emp;

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Arithmetic Expressions

Create expressions on NUMBER and DATE datatypes by using operators.

Add +Subtract -Multiply *Divide /

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Display the annual salary for all employees.

Arithmetic Expressions

SQL> SELECTSQL> SELECT last_name, salary * 12, commission_pctlast_name, salary * 12, commission_pct 2 FROM2 FROM s_emp;s_emp;

SQL> SELECTSQL> SELECT last_name, salary * 12, commission_pctlast_name, salary * 12, commission_pct 2 FROM2 FROM s_emp;s_emp;

LAST_NAMELAST_NAME SALARY*12SALARY*12 COMMISSION_PCTCOMMISSION_PCT------------------------ ------------------------ ----------------------------......HavelHavel 15684 15684MageeMagee 1680016800 1010GiljumGiljum 1788017880 12.512.5SedeghiSedeghi 1818018180 1010NguyenNguyen 1830018300 1515DumasDumas 1740017400 17.517.5MaduroMaduro 1680016800......

LAST_NAMELAST_NAME SALARY*12SALARY*12 COMMISSION_PCTCOMMISSION_PCT------------------------ ------------------------ ----------------------------......HavelHavel 15684 15684MageeMagee 1680016800 1010GiljumGiljum 1788017880 12.512.5SedeghiSedeghi 1818018180 1010NguyenNguyen 1830018300 1515DumasDumas 1740017400 17.517.5MaduroMaduro 1680016800......

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Column Aliases

A column alias renames a column heading.

Especially useful with calculations

Immediately follows column nameOptional AS keyword between column name and alias

Double quotation marks are required if an alias contains spaces, special characters, or is case-sensitive.

SQL> SELECT ename SQL> SELECT ename ""NameName"",,

2 sal2 sal**1212 " "Annual SalaryAnnual Salary""

3 FROM emp;3 FROM emp;

SQL> SELECT ename SQL> SELECT ename ""NameName"",,

2 sal2 sal**1212 " "Annual SalaryAnnual Salary""


SQL> SELECT ename AS name, sal AS salarySQL> SELECT ename AS name, sal AS salary


SQL> SELECT ename AS name, sal AS salarySQL> SELECT ename AS name, sal AS salary


NAME SALARY

------------- ---------

...

Name Annual Salary

------------- -------------

...

Using Column Aliases

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Literal Character String

A literal is a character, expression, or number included in the SELECT list.

Date and character literal values must be enclosed within single quotation marks.

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Concatenation Operator

The concatenation operatorIs represented by two vertical bars (||).(MS Access: & operator)

Links columns or character strings to other columns.

Creates a resultant column that is a character expression.

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Concatenation Operator: Example

EmployeesEmployees----------------------------------------------------------------------------------------Carmen Velasquez, PresidentCarmen Velasquez, PresidentLaDoris Ngao, VP, OperationsLaDoris Ngao, VP, OperationsMidori Nagayama, VP, SalesMidori Nagayama, VP, SalesMark Quick-To-See, VP, FinanceMark Quick-To-See, VP, FinanceAudry Ropeburn, VP, AdministrationAudry Ropeburn, VP, AdministrationMolly Urguhart, Warehouse ManagerMolly Urguhart, Warehouse Manager......

EmployeesEmployees----------------------------------------------------------------------------------------Carmen Velasquez, PresidentCarmen Velasquez, PresidentLaDoris Ngao, VP, OperationsLaDoris Ngao, VP, OperationsMidori Nagayama, VP, SalesMidori Nagayama, VP, SalesMark Quick-To-See, VP, FinanceMark Quick-To-See, VP, FinanceAudry Ropeburn, VP, AdministrationAudry Ropeburn, VP, AdministrationMolly Urguhart, Warehouse ManagerMolly Urguhart, Warehouse Manager......

SQL> SELECTSQL> SELECT first_name ||' '|| last_namefirst_name ||' '|| last_name 22 ||', '|| title "Employees"||', '|| title "Employees" 3 FROM 3 FROM s_emp;s_emp;

SQL> SELECTSQL> SELECT first_name ||' '|| last_namefirst_name ||' '|| last_name 22 ||', '|| title "Employees"||', '|| title "Employees" 3 FROM 3 FROM s_emp;s_emp;

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Managing Null Values in expressions

NULL is a value that is unavailable, unassigned, unknown, or inapplicable.

NULL is not the same as zero or space.

Arithmetic expressions containing a null value evaluate to NULL.

SQL> SELECTSQL> SELECT last_name, title,last_name, title, 22 salary*commission_pct/100 COMMsalary*commission_pct/100 COMM 3 FROM 3 FROM s_emp;s_emp;

SQL> SELECTSQL> SELECT last_name, title,last_name, title, 22 salary*commission_pct/100 COMMsalary*commission_pct/100 COMM 3 FROM 3 FROM s_emp;s_emp;

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NVL Function

Convert NULL to an actual value with NVL.Datatypes to use are date, character, and number.Datatypes must match.

NVL (start_date, '01-JAN-95')NVL (title, 'No Title Yet')NVL (salary, 1000)

SQL> SELECTSQL> SELECT last_name, title,last_name, title, 22 salary*NVL(commission_pct,0)/100 COMMsalary*NVL(commission_pct,0)/100 COMM 3 FROM 3 FROM s_emp;s_emp;

SQL> SELECTSQL> SELECT last_name, title,last_name, title, 22 salary*NVL(commission_pct,0)/100 COMMsalary*NVL(commission_pct,0)/100 COMM 3 FROM 3 FROM s_emp;s_emp;

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Duplicate Rows

The default display of queries is all rows including duplicate rows.

Eliminate duplicate rows by using DISTINCT in the SELECT clause.

SQL> SELECTSQL> SELECT DISTINCT nameDISTINCT name 2 FROM 2 FROM s_dept;s_dept;

SQL> SELECTSQL> SELECT DISTINCT nameDISTINCT name 2 FROM 2 FROM s_dept;s_dept;

SQL> SELECTSQL> SELECT namename 2 FROM 2 FROM s_dept;s_dept;

SQL> SELECTSQL> SELECT namename 2 FROM 2 FROM s_dept;s_dept;

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DISTINCT with Multiple Columns

DISTINCT applies to all columns in the SELECT list.

When DISTINCT is applied to multiple columns, the result represents the distinct combination of the columns.

SQL> SELECT DISTINCT dept_id, titleSQL> SELECT DISTINCT dept_id, title 2 FROM 2 FROM s_emp;s_emp;SQL> SELECT DISTINCT dept_id, titleSQL> SELECT DISTINCT dept_id, title 2 FROM 2 FROM s_emp;s_emp;

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The ORDER BY Clause

Sort rows with the ORDER BY clause.ASC – ascending order, default.DESC – descending order.ORDER BY clause is last in SELECT command.

SQL> SELECTSQL> SELECT last_name, dept_id, start_date last_name, dept_id, start_date 2 FROM 2 FROM s_emp s_emp 3 ORDER BY3 ORDER BY last_name; last_name;

SQL> SELECTSQL> SELECT last_name, dept_id, start_date last_name, dept_id, start_date 2 FROM 2 FROM s_emp s_emp 3 ORDER BY3 ORDER BY last_name; last_name;

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The ORDER BY Clause

The default sort order is ascending.The sort order can be reversed by using DESC.You can sort by expressions or aliases.

Null values are displayedLast for ascending sequences.First for descending sequences.

SQL> SELECTSQL> SELECT last_name EMPLOYEE, start_date last_name EMPLOYEE, start_date 2 FROM 2 FROM s_emp s_emp 3 ORDER BY3 ORDER BY EMPLOYEE DESC; EMPLOYEE DESC;

SQL> SELECTSQL> SELECT last_name EMPLOYEE, start_date last_name EMPLOYEE, start_date 2 FROM 2 FROM s_emp s_emp 3 ORDER BY3 ORDER BY EMPLOYEE DESC; EMPLOYEE DESC;

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Sorting by Multiple Columns

You can order by position to save time.

SQL> SELECTSQL> SELECT last_name, dept_id, salarylast_name, dept_id, salary 2 FROM 2 FROM s_emps_emp 3 ORDER BY3 ORDER BY dept_id, salary DESC;dept_id, salary DESC;

SQL> SELECTSQL> SELECT last_name, dept_id, salarylast_name, dept_id, salary 2 FROM 2 FROM s_emps_emp 3 ORDER BY3 ORDER BY dept_id, salary DESC;dept_id, salary DESC;

SQL> SELECTSQL> SELECT last_name, salary * 12 last_name, salary * 12 2 FROM 2 FROM s_emp s_emp 3 ORDER BY3 ORDER BY 2; 2;

SQL> SELECTSQL> SELECT last_name, salary * 12 last_name, salary * 12 2 FROM 2 FROM s_emp s_emp 3 ORDER BY3 ORDER BY 2; 2;

You can sort by multiple columns

The order of ORDER BY list is order of sort.

You can sort by a column that is not in the SELECT list.

54

SQL : Structured Query Language

Limiting Selected Rows

55

Limiting Rows Selected

Restrict the rows returned by using the WHERE

clause.The WHERE clause follows the FROM clause.Conditions consist of the following:

Column name, expression, constantComparison operatorLiteralSQL> SELECTSQL> SELECT last_name, dept_id, salarylast_name, dept_id, salary

2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE dept_id = 42;dept_id = 42;

SQL> SELECTSQL> SELECT last_name, dept_id, salarylast_name, dept_id, salary 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE dept_id = 42;dept_id = 42;

56

Character Strings and Dates

Character strings and dates are enclosed within single quotation marks.Number values are not enclosed within quotation marks.Character values are case-sensitive.

SQL> SELECTSQL> SELECT first_name, last_name, titlefirst_name, last_name, title 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE last_name = 'Magee';last_name = 'Magee';

SQL> SELECTSQL> SELECT first_name, last_name, titlefirst_name, last_name, title 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE last_name = 'Magee';last_name = 'Magee';

57

Comparison and Logical Operators

Logical comparison operators= > >= < <=

SQL comparison operatorsBETWEEN ... AND...IN(list)LIKEIS NULL

Logical operatorsANDORNOT

58

Negating Expressions

Sometimes it is easier to exclude rows you know you do not want.Logical Operators

!= <> ^=

SQL OperatorsNOT BETWEENNOT INNOT LIKEIS NOT NULL

59

BETWEEN and IN SQL Operators

Use the BETWEEN operator to test for values between, and inclusive of, a range of values.

SQL> SELECTSQL> SELECT id, name, region_idid, name, region_id 2 FROM 2 FROM s_depts_dept 3 WHERE3 WHERE region_id IN (1,3);region_id IN (1,3);

SQL> SELECTSQL> SELECT id, name, region_idid, name, region_id 2 FROM 2 FROM s_depts_dept 3 WHERE3 WHERE region_id IN (1,3);region_id IN (1,3);

SQL> SELECTSQL> SELECT first_name, last_name, start_datefirst_name, last_name, start_date 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE start_date BETWEEN '09-may-91'start_date BETWEEN '09-may-91' 4 4 AND '17-jun-91';AND '17-jun-91';

SQL> SELECTSQL> SELECT first_name, last_name, start_datefirst_name, last_name, start_date 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE start_date BETWEEN '09-may-91'start_date BETWEEN '09-may-91' 4 4 AND '17-jun-91';AND '17-jun-91';

• Use IN to test for values in a list.Use IN to test for values in a list.

Use IN to test for values in a list.

60

LIKE SQL Operator

You can use the LIKE operator to perform wildcard searches of valid search string values.

Search conditions can contain either literal characters or numbers.

"%" denotes none or many characters."_" denotes one character.

SQL> SELECTSQL> SELECT last_namelast_name 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE last_name LIKE 'M%';last_name LIKE 'M%';

SQL> SELECTSQL> SELECT last_namelast_name 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE last_name LIKE 'M%';last_name LIKE 'M%';

61

LIKE SQL Operator

The LIKE operator can be used as a shortcut for some BETWEEN comparisons.

You can combine pattern matching characters.SQL> SELECTSQL> SELECT last_namelast_name 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE last_name LIKE '_a%';last_name LIKE '_a%';

SQL> SELECTSQL> SELECT last_namelast_name 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE last_name LIKE '_a%';last_name LIKE '_a%';

SQL> SELECTSQL> SELECT last_name, start_datelast_name, start_date 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE start_date LIKE '%91';start_date LIKE '%91';

SQL> SELECTSQL> SELECT last_name, start_datelast_name, start_date 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE start_date LIKE '%91';start_date LIKE '%91';

62

IS NULL SQL Operator

Test for null values with the IS NULL operator.Do not use the = operator.SQL> SELECTSQL> SELECT id, name, credit_ratingid, name, credit_rating 2 FROM 2 FROM s_customers_customer 3 WHERE3 WHERE sales_rep_id IS NULL;sales_rep_id IS NULL;

SQL> SELECTSQL> SELECT id, name, credit_ratingid, name, credit_rating 2 FROM 2 FROM s_customers_customer 3 WHERE3 WHERE sales_rep_id IS NULL;sales_rep_id IS NULL;

63

Multiple Conditions

Use complex criteria.Combine conditions with AND or OR operators.AND requires both conditions to be TRUE.

• OR requires either condition to be TRUE.OR requires either condition to be TRUE.

SQL> SELECTSQL> SELECT last_name, salary, dept_id, titlelast_name, salary, dept_id, title 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE dept_id = 41dept_id = 41 4 AND4 AND title = 'Stock Clerk';title = 'Stock Clerk';

SQL> SELECTSQL> SELECT last_name, salary, dept_id, titlelast_name, salary, dept_id, title 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE dept_id = 41dept_id = 41 4 AND4 AND title = 'Stock Clerk';title = 'Stock Clerk';

SQL> SELECTSQL> SELECT last_name, salary, dept_id, titlelast_name, salary, dept_id, title 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE dept_id = 41dept_id = 41 4 OR4 OR title = 'Stock Clerk';title = 'Stock Clerk';

SQL> SELECTSQL> SELECT last_name, salary, dept_id, titlelast_name, salary, dept_id, title 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE dept_id = 41dept_id = 41 4 OR4 OR title = 'Stock Clerk';title = 'Stock Clerk';

64

Rules of Precedence

Order Evaluated Operator1 All comparison

operators.2 AND3 OR

Override rules of precedence by using Override rules of precedence by using parentheses.parentheses.

65

Display information for those employees in department 44 who earn 1000 or more, and any employees in department 42.

SQL> SELECTSQL> SELECT last_name, salary, dept_idlast_name, salary, dept_id 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE salary >= 1000salary >= 1000 4 AND4 AND dept_id = 44dept_id = 44 5 OR5 OR dept_id = 42;dept_id = 42;

SQL> SELECTSQL> SELECT last_name, salary, dept_idlast_name, salary, dept_id 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE salary >= 1000salary >= 1000 4 AND4 AND dept_id = 44dept_id = 44 5 OR5 OR dept_id = 42;dept_id = 42;

Rules of Precedence: Examples

SQL> SELECTSQL> SELECT last_name, salary, dept_idlast_name, salary, dept_id 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE salary >= 1000salary >= 1000 4 AND4 AND (dept_id = 44(dept_id = 44 5 OR5 OR dept_id = 42);dept_id = 42);

SQL> SELECTSQL> SELECT last_name, salary, dept_idlast_name, salary, dept_id 2 FROM 2 FROM s_emps_emp 3 WHERE3 WHERE salary >= 1000salary >= 1000 4 AND4 AND (dept_id = 44(dept_id = 44 5 OR5 OR dept_id = 42);dept_id = 42);

Display information for those employees in department 44 or 42 who earn 1000 or more.

66

Summary – Selecting Rows

SELECTSELECT [DISTINCT] {*, [DISTINCT] {*, column column [[aliasalias], ...}], ...}FROM FROM tabletable[WHERE[WHERE condition(s)condition(s)]][ORDER BY[ORDER BY {{column, expr, aliascolumn, expr, alias} [ASC|DESC]];} [ASC|DESC]];

SELECTSELECT [DISTINCT] {*, [DISTINCT] {*, column column [[aliasalias], ...}], ...}FROM FROM tabletable[WHERE[WHERE condition(s)condition(s)]][ORDER BY[ORDER BY {{column, expr, aliascolumn, expr, alias} [ASC|DESC]];} [ASC|DESC]];

67

68

Single Row Functions

69

Overview of Functions in SQL

Use functions toPerform calculations on data.Modify individual data items.Manipulate output for groups of rows.Alter date formats for display.Convert column data types.

70

Two Types of SQL Functions

Single row functionsCharacterNumberDateConversion

Multiple row functionsGroup

SINGLESINGLEROWROW

MULTIMULTIROWROW

FUNCTIONFUNCTION

71

Single Row Functions: Syntax

Single row functionsManipulate data items.Accept arguments and return one value.Act on each row returned.Return one result per row.Modify the datatype.Can be nested.

Syntax

function_name function_name ((columncolumn||expressionexpression, [, [arg1, arg2,...arg1, arg2,...])])function_name function_name ((columncolumn||expressionexpression, [, [arg1, arg2,...arg1, arg2,...])])

72

Character Functions

LOWER Converts to lowercaseUPPER Converts to uppercaseINITCAP Converts to initial capitalizationCONCAT Concatenates valuesSUBSTR Returns substringLENGTH Returns number of characters

73

Character Manipulation Functions

Manipulate character strings

CONCAT('Good', 'String') GoodStringSUBSTR('String',1,5) StrinSUBSTR('String',3) ringLENGTH('String') 6

74

Number Functions

ROUND Rounds value to specified decimalTRUNC Truncates value to specified decimalMOD Returns remainder of divisionPOWER Returns the power

75

ROUND and TRUNC Functions

ROUND (45.923, 2) 45.92ROUND (45.923, 0) 46ROUND (45.923, -1) 50TRUNC (45.923, 2) 45.92TRUNC (45.923) 45TRUNC (45.923, -1) 40

76

Oracle Date Format

Oracle stores dates in an internal numeric format.

Century, year, month, day, hours, minutes, seconds

Default date display is DD-MON-YY.

SYSDATE is a function returning date and time.

DUAL is a dummy table used to view SYSDATE.

77

Arithmetic Operators with Dates

Add or subtract a number to or from a date for a resultant date value.

Subtract two dates to find the number of days between those dates.

Add hours to a date by dividing the number of hours by 24.

78

Date Functions

MONTHS_BETWEEN Number of monthsbetween two dates

ADD_MONTHS Add calendar months

to dateNEXT_DAY Next day of the date

specifiedLAST_DAY Last day of the month

79

Date Functions

MONTHS_BETWEEN(to_date(’01-JAN-2003’, ’DD-MON-YYYY’),to_date(’14-Mar-2003’, ’DD-MON-YYYY’))

-2.429354838ADD_MONTHS('11-JAN-94',6)

'11-JUL-94'NEXT_DAY('01-SEP-95','FRIDAY')

'08-SEP-95'

LAST_DAY('01-SEP-95')'30-SEP-

95'

80

Conversion Functions: Overview

TO_CHAR converts a number or date string to a character string.

TO_NUMBER converts a character string containing digits to a number.

TO_DATE converts a character string of a date to a date value.

Conversion functions can use a format model composed of many elements.

81

Summary

Single row functions can be nested to any level.Single row functions work on character, number, and date data.Conversion functions are TO_CHAR, TO_DATE, and TO_NUMBER.SYSDATE is a pseudo-column used to return current date and time.DUAL is a dummy table in the database.

82

Group Functions

83

Group Functions

Group functions operate on sets of rows to give one result per group.Group functions appear in both SELECT lists and HAVING clauses.The GROUP BY clause in the SELECT statement divides rows into smaller groups.The HAVING clause restricts result groups.

84

GROUP BY and HAVING Clauses in the SELECT Statement: Syntax

GROUP BY divides rows into smaller groups.HAVING further restricts the result groups.

SELECTSELECT columncolumn, , group_functiongroup_function

FROMFROM tabletable

[WHERE[WHERE conditioncondition]]

[GROUP BY[GROUP BY group_by_expressiongroup_by_expression]]

[HAVING[HAVING group_conditiongroup_condition]]

[ORDER BY[ORDER BY columncolumn];];


FROMFROM tabletable





85

Group Functions

AVG (DISTINCT|ALL|n)COUNT (DISTINCT|ALL|expr|*)MAX (DISTINCT|ALL|expr)MIN (DISTINCT|ALL|expr)SUM (DISTINCT|ALL|n)

86

Group Functions: Example

You can use MAX and MIN for any datatype.

SQL> SELECTSQL> SELECT MIN(last_name), MAX(last_name)MIN(last_name), MAX(last_name)

2 FROM2 FROM s_emps_emp;;

SQL> SELECTSQL> SELECT MIN(last_name), MAX(last_name)MIN(last_name), MAX(last_name)

2 FROM2 FROM s_emps_emp;;

SQL> SELECTSQL> SELECT AVG(salary), MAX(salary),AVG(salary), MAX(salary),

22 MIN(salary), SUM(salary)MIN(salary), SUM(salary)

3 FROM3 FROM s_emps_emp

4 WHERE4 WHERE UPPER(title) LIKE 'SALES%';UPPER(title) LIKE 'SALES%';

SQL> SELECTSQL> SELECT AVG(salary), MAX(salary),AVG(salary), MAX(salary),

22 MIN(salary), SUM(salary)MIN(salary), SUM(salary)


4 WHERE4 WHERE UPPER(title) LIKE 'SALES%';UPPER(title) LIKE 'SALES%';

You can use AVG and SUM against columns that can store numeric data.

87

The GROUP BY Clause: Syntax

Divide rows in a table into smaller groups by using the GROUP BY clause.Include the column list in the GROUP BY clause if columns are used in the SELECT clause.Override the default sort order by using the ORDER BY clause.


FROMFROM tabletable





FROMFROM tabletable




88

The GROUP BY Clause: Example

The GROUP BY clause The GROUP BY clause displays one line of data displays one line of data for each department for each department retrieved in the WHERE retrieved in the WHERE clause, and COUNT(*) clause, and COUNT(*) displays the number of displays the number of employees in each employees in each department (group) department (group) displayed.displayed.

SQL> SELECTSQL> SELECT dept_id, COUNT(*) ”Number” dept_id, COUNT(*) ”Number”

2 FROM 2 FROM s_emps_emp

3 WHERE 3 WHERE dept_id = 41dept_id = 41

4 GROUP BY 4 GROUP BY dept_id;dept_id;

SQL> SELECTSQL> SELECT dept_id, COUNT(*) ”Number” dept_id, COUNT(*) ”Number”

2 FROM 2 FROM s_emps_emp

3 WHERE 3 WHERE dept_id = 41dept_id = 41

4 GROUP BY 4 GROUP BY dept_id;dept_id;

DEPT_ID Number DEPT_ID Number

------- ------------- ------

41 4 41 4

DEPT_ID Number DEPT_ID Number

------- ------------- ------

41 4 41 4

89

The GROUP BY Clause: Example

All columns in the SELECT list that are not in group functions must be in the GROUP BY clause.The GROUP BY column does not have to be in the SELECT clause.The results are more meaningful if the GROUP BY column is in the SELECT clause.

SQL> SELECTSQL> SELECT title, MAX(salary)title, MAX(salary)


3 GROUP BY3 GROUP BY title;title;

SQL> SELECTSQL> SELECT title, MAX(salary)title, MAX(salary)


3 GROUP BY3 GROUP BY title;title;

90

Groups Within Groups: Example

Return summary results for groups and subgroups by listing more than one GROUP BY column.Determine the default sort order of the results by the order of the columns in the GROUP BY clause.SQL> SELECTSQL> SELECT dept_id, title, COUNT(*)dept_id, title, COUNT(*)


3 GROUP BY3 GROUP BY dept_id, title;dept_id, title;

SQL> SELECTSQL> SELECT dept_id, title, COUNT(*)dept_id, title, COUNT(*)


3 GROUP BY3 GROUP BY dept_id, title;dept_id, title;

91

SQL> SELECTSQL> SELECT title, 12 * AVG(salary) AS ”ANNUAL SALARY”,title, 12 * AVG(salary) AS ”ANNUAL SALARY”, 2 2 COUNT(*) COUNT(*) AS ”NUMBER OF EMPLOYEES”AS ”NUMBER OF EMPLOYEES” 3 FROM 3 FROM s_emps_emp 4 GROUP BY 4 GROUP BY titletitle 5 HAVING 5 HAVING COUNT(*) > 2;COUNT(*) > 2;

SQL> SELECTSQL> SELECT title, 12 * AVG(salary) AS ”ANNUAL SALARY”,title, 12 * AVG(salary) AS ”ANNUAL SALARY”, 2 2 COUNT(*) COUNT(*) AS ”NUMBER OF EMPLOYEES”AS ”NUMBER OF EMPLOYEES” 3 FROM 3 FROM s_emps_emp 4 GROUP BY 4 GROUP BY titletitle 5 HAVING 5 HAVING COUNT(*) > 2;COUNT(*) > 2;

Display Specific Groups by Using the HAVING Clause

TITLETITLE ANNUAL SALARYANNUAL SALARY NUMBER OF EMPLOYEESNUMBER OF EMPLOYEES---------------------------------------- ---------------------------- --------------------------------------Sales RepresentativeSales Representative $17,712.00$17,712.00 55Stock ClerkStock Clerk $11,388.00$11,388.00 1010Warehouse ManagerWarehouse Manager $14,776.80$14,776.80 55

HAVING clause (Restrict Groups)HAVING clause (Restrict Groups)

Display specific groups of job titles as Display specific groups of job titles as restricted in the HAVING clause.restricted in the HAVING clause.

92

The HAVING Clause: Syntax

Use the HAVING clause to further restrict groups.

Step 1: Rows are grouped.Step 2: The group function is applied to the group.Step 3: Groups matching the HAVING condition are displayed.


FROMFROM tabletable






FROMFROM tabletable





93

94

Displaying Data from Multiple Tables

95

Joining Tables - What Is a Join?

A join is used to query data from more than one table.Rows are joined using common values, typically primary and foreign key values.Join methods

EquijoinNon-equijoinOuter joinSelf joinSet operators

96

S_EMP TableS_EMP TableID LAST_NAME ID LAST_NAME DEPT_IDDEPT_ID-- --------------- --------- --------------- ------- 1 Velasquez1 Velasquez 5050 2 Ngao2 Ngao 4141 3 Nagayama3 Nagayama 3131 4 Quick-To-See4 Quick-To-See 1010 5 Ropeburn5 Ropeburn 5050 6 Urguhart6 Urguhart 4141 7 Menchu7 Menchu 4242 8 Biri8 Biri 4343 9 Catchpole9 Catchpole 444410 Havel10 Havel 454511 Magee11 Magee 313112 Giljum12 Giljum 323213 Sedeghi13 Sedeghi 333314 Nguyen14 Nguyen 343415 Dumas15 Dumas 353516 Maduro16 Maduro 4141

S_EMP TableS_EMP TableID LAST_NAME ID LAST_NAME DEPT_IDDEPT_ID-- --------------- --------- --------------- ------- 1 Velasquez1 Velasquez 5050 2 Ngao2 Ngao 4141 3 Nagayama3 Nagayama 3131 4 Quick-To-See4 Quick-To-See 1010 5 Ropeburn5 Ropeburn 5050 6 Urguhart6 Urguhart 4141 7 Menchu7 Menchu 4242 8 Biri8 Biri 4343 9 Catchpole9 Catchpole 444410 Havel10 Havel 454511 Magee11 Magee 313112 Giljum12 Giljum 323213 Sedeghi13 Sedeghi 333314 Nguyen14 Nguyen 343415 Dumas15 Dumas 353516 Maduro16 Maduro 4141

Relations Between Tables

S_DEPT TableS_DEPT TableID NAME REGION_IDID NAME REGION_ID-- --------------- ----------- --------------- ---------30 Finance 130 Finance 131 Sales 131 Sales 132 Sales 232 Sales 243 Operations 343 Operations 350 Administration 150 Administration 1

S_DEPT TableS_DEPT TableID NAME REGION_IDID NAME REGION_ID-- --------------- ----------- --------------- ---------30 Finance 130 Finance 131 Sales 131 Sales 132 Sales 232 Sales 243 Operations 343 Operations 350 Administration 150 Administration 1S_REGION TableS_REGION Table

ID NAMEID NAME-- ----------------------- --------------------- 1 North America1 North America 2 South America2 South America 3 Africa / Middle East3 Africa / Middle East 4 Asia4 Asia 5 Europe5 Europe

S_REGION TableS_REGION TableID NAMEID NAME-- ----------------------- --------------------- 1 North America1 North America 2 South America2 South America 3 Africa / Middle East3 Africa / Middle East 4 Asia4 Asia 5 Europe5 Europe

97

Cartesian Product

The results of a cartesian product are displayed when

A join condition is omitted.A join condition is invalid.All rows in the first table are joined to all rows in the second table.

To avoid a Cartesian product, always include a valid join condition in a WHERE clause.

98

Simple Join Query: Syntax

Write the join condition in the WHERE clause.

Precede each column name with the table name for clarity.

Column names must be prefixed with the table name when the same column name appears in more than one table.

SELECTSELECT table.column, table.columntable.column, table.column

FROMFROM table1, table2table1, table2

WHEREWHERE table1.column1 = table2.column2table1.column1 = table2.column2;;



WHEREWHERE table1.column1 = table2.column2table1.column1 = table2.column2;;

99

Equijoin: Columns must match

S_EMPS_EMP S_DEPTS_DEPT

ServerServer

LAST_NAME LAST_NAME DEPT_IDDEPT_ID IDID NAMENAME------------------ -------------- ---- ------------------------------VelasquezVelasquez 5050 5050 AdministrationAdministrationNgaoNgao 4141 4141 OperationsOperationsNagayamaNagayama 3131 3131 SalesSalesRopeburnRopeburn 5050 5050 AdministrationAdministrationUrguhartUrguhart 4141 4141 OperationsOperationsMenchuMenchu 4242 4242 OperationsOperationsBiriBiri 4343 4343 OperationsOperationsHavelHavel 4545 4545 OperationsOperations...... ......

100

Equijoin: Example

Equijoins are most often used when a column in one table corresponds directly to a column in another table.The join condition includes the equal (=) operator.

Alternative (new) syntax:

SQL> SELECT e.ename, e.job, e.sal, d.dnameSQL> SELECT e.ename, e.job, e.sal, d.dname

22 FROM emp e, dept dFROM emp e, dept d

33 WHERE e.deptno = d.deptno;WHERE e.deptno = d.deptno;


22 FROM emp e, dept dFROM emp e, dept d

33 WHERE e.deptno = d.deptno;WHERE e.deptno = d.deptno;


22 FROM emp e INNER JOIN dept dFROM emp e INNER JOIN dept d

33 ON e.deptno = d.deptno;ON e.deptno = d.deptno;


22 FROM emp e INNER JOIN dept dFROM emp e INNER JOIN dept d

33 ON e.deptno = d.deptno;ON e.deptno = d.deptno;

101

Qualifying Ambiguous Column Names

Use table prefixes to qualify column names that are in multiple tables.

Improve performance by using table prefixes.

Distinguish columns that have identical names but reside in different tables by using column aliases.

102

Non-Equijoins: Example

Non-equijoins result when no column in one table corresponds directly to a column in the second table.

The join condition contains an operator other than equal (=).

SQL> SELECT e.ename, e.job, e.sal, s.gradeSQL> SELECT e.ename, e.job, e.sal, s.grade

22 FROM emp e, salgrade sFROM emp e, salgrade s

33 WHERE e.sal BETWEEN s.losal AND s.hisal;WHERE e.sal BETWEEN s.losal AND s.hisal;

SQL> SELECT e.ename, e.job, e.sal, s.gradeSQL> SELECT e.ename, e.job, e.sal, s.grade

22 FROM emp e, salgrade sFROM emp e, salgrade s

33 WHERE e.sal BETWEEN s.losal AND s.hisal;WHERE e.sal BETWEEN s.losal AND s.hisal;

103

Outer Joins: Old Syntax

Use an outer join to see rows that do not normally meet the join condition.Outer join operator is the plus sign (+).Place the operator on the side of the join where there is no value to join to.



WHEREWHERE table1.column(+) = table2.columntable1.column(+) = table2.column;;



WHEREWHERE table1.column(+) = table2.columntable1.column(+) = table2.column;;

104

Outer Joins: New Syntax

Use LEFT JOIN or RIGHT JOIN operators instead of INNER JOIN.LEFT JOIN returns all rows in first table.

RIGHT JOIN returns all rows in second table.


FROMFROM table1 LEFT JOIN table2table1 LEFT JOIN table2

ONON table1.column = table2.columntable1.column = table2.column;;


FROMFROM table1 LEFT JOIN table2table1 LEFT JOIN table2



FROMFROM table1 RIGHT JOIN table2table1 RIGHT JOIN table2



FROMFROM table1 RIGHT JOIN table2table1 RIGHT JOIN table2


105

Outer join - Exemple

Select Employee.Num, Employee.name, Office.ONum, Office.Buildfrom Employee, Officewhere Employee.NumOff= Office.ONum(+);

or :

Select Employee. Num, Employee.name, Office.ONum, Office.Build from Employee LEFT JOIN OfficeON Employee.NumOff= Office.ONum

Employee OfficeNum Name NumOff ONum Build23 Toto 47 40 A183 Babette 18 42 B369 Loulou 03 47 A170 Marie 40 62 C1

Num Name ONum Build

23 Toto 47 A1

83 Babette 18 69 Loulou 03 70 Marie 40 A1

23

106

Self Joins: Example

Join rows in a table to rows in the same table by using a self join.Simulate two tables in the FROM clause by creating two aliases for the table.

SQL> SELECTSQL> SELECT worker.last_name||' works for '||worker.last_name||' works for '||

2 2 manager.last_namemanager.last_name

3 FROM3 FROM s_emp worker, s_emp managers_emp worker, s_emp manager

4 WHERE4 WHERE worker.manager_id = manager.id;worker.manager_id = manager.id;

SQL> SELECTSQL> SELECT worker.last_name||' works for '||worker.last_name||' works for '||

2 2 manager.last_namemanager.last_name

3 FROM3 FROM s_emp worker, s_emp managers_emp worker, s_emp manager

4 WHERE4 WHERE worker.manager_id = manager.id;worker.manager_id = manager.id;

107

Summary

You can use multiple methods to join tables:EquijoinNon-equijoinOuter joinSelf join

Create a Cartesian product if you omit the WHERE clause.

Speed up database access with table aliases.

Use aliases to set up self joins.

108

Operations on Result Sets

109

Sometimes it is useful to combine query results from two or more queries into a single result.

SQL supports three set operators which have the pattern

The set operators are:UNIONINTERSECTMINUS

<select statement1><select statement1>

<set operator><set operator>

<select statement 2>;<select statement 2>;

<select statement1><select statement1>

<set operator><set operator>

<select statement 2>;<select statement 2>;

110

Union

Combine two companies customer lists where they have names in common so that the final list has no duplicate names

Column attributes must be the same

Can include more than two tables where applicable

SELECTSELECT <COLUMN> <COLUMN> [AS [AS “Column names”“Column names”]] FROMFROM customer customerUNIONUNION SELECTSELECT <COLUMN> <COLUMN> FROMFROM CUSTOMER_2; CUSTOMER_2;

SELECTSELECT <COLUMN> <COLUMN> [AS [AS “Column names”“Column names”]] FROMFROM customer customerUNIONUNION SELECTSELECT <COLUMN> <COLUMN> FROMFROM CUSTOMER_2; CUSTOMER_2;

SELECTSELECT <COLUMN NAMES> <COLUMN NAMES> FROMFROM T1 T1 UNIONUNION SELECTSELECT <COLUMN NAMES> <COLUMN NAMES> FROMFROM T2 T2 UNIONUNIONSELECTSELECT <COLUMN NAMES> <COLUMN NAMES> FROMFROM T3; T3;

SELECTSELECT <COLUMN NAMES> <COLUMN NAMES> FROMFROM T1 T1 UNIONUNION SELECTSELECT <COLUMN NAMES> <COLUMN NAMES> FROMFROM T2 T2 UNIONUNIONSELECTSELECT <COLUMN NAMES> <COLUMN NAMES> FROMFROM T3; T3;

111

UNION Query Result

SELECTSELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_1 CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_1UNIONUNIONSELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_2;SELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_2;

SELECTSELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_1 CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_1UNIONUNIONSELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_2;SELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_2;

112

UNION ALL Query ResultUNION ALL merges the tables but keeps duplicates in the result table

SELECTSELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_1 CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_1UNION ALLUNION ALLSELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_2;SELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_2;

SELECTSELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_1 CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_1UNION ALLUNION ALLSELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_2;SELECT CUS_LNAME, CUS_FNAME, … FROM CUSTOMER_2;

113

Intersection - Example

Number and names of managers who are engineers

select n°Employee, namefrom Engineerintersectselect n°Employee, namefrom Manager

UEngineerManager

Engineer Managern°Employee name n°Employee name

10 Toto 13 Babette12 Jojo 14 Loulou13 Babette 15 Lolo15 Lolo

n°Employee name13 Babette15 Lolo

114

Difference - Example

Names of the students that didn’t assist

-select nameId, UV from Inscribedminusselect nameId, UVfrom Attendance

Inscribed AttendancenameId UV nameId UV

Toto Maths Toto MathsJojo Maths Jojo MathsToto Physics Babette comp

Babette compJojo comp

nomId UVToto PhysicsJojo comp

115

Remark

Union, intersection and difference need to have relations with the same data types.

These operators are frequently used after projections in order to have these same domains

116

Subqueries

117

What Is a Subquery?

SELECT Syntax

SELECT...SELECT...

FROM...FROM...

WHERE...WHERE...SELECT Syntax

(SELECT...(SELECT...

FROM...FROM...

WHERE...);WHERE...);

Main Main QueryQuery

SubquerySubquery

A subquery is a SELECT statement embedded in a clause of another SQL statement.

118

Subqueries: Syntax

The subquery executes once before the main query.The result of the subquery is used by the main outer query.

SELECTSELECT select_listselect_listFROMFROM tabletableWHEREWHERE expr operatorexpr operator

(SELECT(SELECT select_listselect_list FROMFROM tabletable););



119

How Are Nested Subqueries Processed?

SELECTSELECT dept_iddept_idFROMFROM s_emps_empWHEREWHERE last_name='Biri';last_name='Biri';

Nested QueryNested Query

SELECTSELECT last_name, titlelast_name, titleFROMFROM s_emps_empWHEREWHERE dept_iddept_id = =

Main QueryMain Query

4343

1. Nested SELECT statement is executed first.2. Result is passed into condition of main

query.

120

Single Row Subqueries

SELECT last_name, titleSELECT last_name, titleFROM FROM s_emp s_empWHERE WHERE title = title =

SELECT titleSELECT titleFROM FROM s_emp s_empWHERE WHERE last_name = ’Smith’ last_name = ’Smith’

SQL> SELECT last_name, titleSQL> SELECT last_name, title 2 FROM s_emp 2 FROM s_emp 3 WHERE title = 3 WHERE title = 4 4 (SELECT title (SELECT title 5 5 FROM s_emp FROM s_emp 6 6 WHERE last_name = ’Smith’); WHERE last_name = ’Smith’);

Write the SQLWrite the SQLstatement tostatement todisplay thedisplay thelast name last name and title of and title of an employee.an employee.

Write the SQLWrite the SQLstatement tostatement tofind out find out Smith’s title.Smith’s title.

Put bothPut bothstatementsstatementstogether and together and let SQL let SQL determinedeterminethe title forthe title forSmith.Smith.

121

Multiple Row Subqueries: Example

A multiple row subquery returns many rows.You must use a multiple row operator in the WHERE clause, for example the [NOT]IN operator.

SQL> SELECTSQL> SELECT last_name, first_name, titlelast_name, first_name, title 2 FROM2 FROM s_emps_emp 3 WHERE3 WHERE dept_in INdept_in IN 44 (SELECT(SELECT IDID 55 FROMFROM s_depts_dept66 WHERE name = 'Finance'WHERE name = 'Finance'77 OR region_id = 2); OR region_id = 2);

SQL> SELECTSQL> SELECT last_name, first_name, titlelast_name, first_name, title 2 FROM2 FROM s_emps_emp 3 WHERE3 WHERE dept_in INdept_in IN 44 (SELECT(SELECT IDID 55 FROMFROM s_depts_dept66 WHERE name = 'Finance'WHERE name = 'Finance'77 OR region_id = 2); OR region_id = 2);

122

Summary

Subqueries are useful when a query is based on unknown values.A subquery contains more than one SELECT statement.





123

Chapter 2. SQL*plus

124

What is it?

SQL*PLUS is an Oracle interactive user interface with application language

Typically used to issue ad-hoc queries and to view the query result on the screen

Provides an interactive environment that allows users to:

Connect to and disconnect from a database;Analyze SQL statements;Control the output format;Execute a bunch of SQL statements from a file.

125

Logging in to SQL*Plus

From a windows environment Double-click the icon. Fill in username and password.

From command line sqlplus [username[/password]]

126

Entering Commands in SQL*Plus

SQL commands to manipulate data and database structures

SQL*Plus commands to format query results, edit commands, and create variables

PL/SQL blocks to execute procedural statements

An SQL statement must always be terminated by a semicolon (;)SQL*Plus commands need not be terminated by a semicolon. Upper and lower case letters are only important for string comparisons.

127

Comparison of SQL and SQL*Plus Commands

Communicates with Oracle Server.Uses database commands - SELECT.Is stored in the SQL buffer.Uses functions to perform formatting.

• Recognizes SQL Recognizes SQL commands.commands.

• Is not a database Is not a database command language.command language.

• Is not stored in the Is not stored in the SQL buffer.SQL buffer.

• Uses commands to Uses commands to format data.format data.

SQLSQL SQL*PlusSQL*Plus

128

How to Get HELP

SQLPLUS commands are described in SQLPLUS Help system

SQL> HELP indexThis command returns list of all SQLPLUS commands

SQL> HELP Command

129

Useful SQLPLUS Commands

Current SQL statement is stored in a buffer To display the buffer content use L[IST] command

To modify buffer content use CHANGE commandC[HANGE] /old_string/new_string/

To re-execute the statement from the bufferSQL> /

Or SQL> R[UN]

130

Other Useful SQLPLUS Commands

SAVE [REPLACE | APPEND] saves buffer content into a file on the host

DESC[RIBE] displays table’s definition (its fields and data types)

DESC Table_name;

NOT NULL columns must contain data. Example column data type and length

NUMBER (p,s)VARCHAR2(s)DATECHAR(s)

SAVE SAVE File_name.sql [REPLACE|APPEND];File_name.sql [REPLACE|APPEND];SAVE SAVE File_name.sql [REPLACE|APPEND];File_name.sql [REPLACE|APPEND];

131


GET loads the file content from the host into statement buffer

GET File_name.sql;

The statement can be re-executed by “/” command or “RUN”

To execute a statement from a file without GET command@File_name.sql;

Or start File_name.sql;

132

Editors

ED[IT] invokes an editor and loads the current buffer into the editor.

EDIT File_name;Invokes the editor and load the file into it

After exiting the editor, the modified SQL statement is stored in the buffer and can be executed

(command run).

133


SET PAUSE commandAllows you to control scrolling of your terminal. You must press [Return] after seeing each pause.

SET LINESIZE Controls the length of line

An SQL query can always be interrupted by using <Control>C.

To exit SQL*Plus you can either type exit or quit.

SET PAUSE {OFF|ON| text}SET PAUSE {OFF|ON| text}SET PAUSE {OFF|ON| text}SET PAUSE {OFF|ON| text}

134

SQL*Plus User Variables

A SQL*Plus user variable is a CHAR variable, which can be assigned a string value.User variables can be defined as substitution variable in SQL statementsAn ampersand (&) precedes the substitution variable inside a SQL statement.SELECT * SELECT *

FROM s_dept FROM s_dept

WHERE region_id = &id;WHERE region_id = &id;

Enter value for id: 2Enter value for id: 2

......

SELECT * SELECT *

FROM s_dept FROM s_dept

WHERE region_id = &id;WHERE region_id = &id;

Enter value for id: 2Enter value for id: 2

......

135

SQL*Plus User Variables

DEFINE variable [ = text ]Defines a CHAR user variable and stores input from the user into the variable.

UNDEFINE variable Erases the user variable.

DEFINE id = 2DEFINE id = 2

SELECT * FROM s_dept WHERE region_id = &id;SELECT * FROM s_dept WHERE region_id = &id;

... ...

UNDEFINE idUNDEFINE id

DEFINE id = 2DEFINE id = 2

SELECT * FROM s_dept WHERE region_id = &id;SELECT * FROM s_dept WHERE region_id = &id;

... ...

UNDEFINE idUNDEFINE id

136

Record Your Session

SPOOL file_nameThe command records SQL statements, SQLPLUS commands and system’s responses to the specified file (.lst)

SPOOL OFF – stops spooling

SPOOL OUT – stops spooling and sends the file to the printer

137

Chapter 3.

PL/SQL: Procedural Language SQL

138

What is PL/SQL?

PL/SQL is an extension to SQL with design features of programming languages.Data manipulation and query statements are included within procedural units of code.

Benefits of PL/SQLModularize program developmentDeclare identifiersProgram with procedural language control structuresHandle errorsImprove performance

Introduction

139

Why PL/SQL

Oracle Database Server

Client Application Server

SQL SQL SQL

140

SQL

Program resides on client machineLots of requests to database serverRequests made through SQLEach request sends back information

One network trip for each SQL request

141

Why PL/SQL

Oracle Database Server

Client Application Server

Call PL/SQL prog

Call PL/SQL prog

Call PL/SQL prog

PL/SQL prog------------

SQLSQLSQLSQL

142

Pl/SQL sits inside database

Programs reside on client machinesRequests DB server to run PL/SQL programSeveral SQL statements bundled together as a single PL/SQL blockRun as a single unitIntermediate operation results stay on database serverResults sent backLess network traffic

143

PL/SQL Block Structure

[DECLARE] -- OptionalVariables, constants, cursors, user-defined exceptions

BEGIN -- MandatorySQL statementsPL/SQL control statements

[EXCEPTION ] -- OptionalActions to perform when errors occur

END; -- Mandatory

[DECLARE] -- OptionalVariables, constants, cursors, user-defined exceptions

BEGIN -- MandatorySQL statementsPL/SQL control statements

[EXCEPTION ] -- OptionalActions to perform when errors occur

END; -- Mandatory

144

Example PL/SQL Block

DECLARE v_product_id s_product.id%TYPE;BEGIN SELECT idINTO v_product_idFROM s_productWHERE id = &p_product_id; DELETE FROM s_inventoryWHERE product_id = v_product_id; COMMIT;EXCEPTION WHEN OTHERS THENROLLBACK;INSERT INTO exception_table (message)VALUES ('Some error occurred in the database.');COMMIT;END;

DECLARE v_product_id s_product.id%TYPE;BEGIN SELECT idINTO v_product_idFROM s_productWHERE id = &p_product_id; DELETE FROM s_inventoryWHERE product_id = v_product_id; COMMIT;EXCEPTION WHEN OTHERS THENROLLBACK;INSERT INTO exception_table (message)VALUES ('Some error occurred in the database.');COMMIT;END;

145

Program Structure

May span multiple text editor lines

Each line ends with a semicolon

Text is not case sensitive

Comments /* */

Single line comments --

146

Data Types

integer --signed integernumber(p,n)realchar(n) varchar2(n)boolean – true or falsedate

147

Variable declaration

name datatype [not null] [ := value ]name [constant] datatype := valueNote:

assignment is :=Constants and not nulls must be initialized with a value

instead of standard datatype we can use:name%type

where name is a column or variable name whose type you want to use.

for example: id employees.empID%type

foo integer not null := 20;

pi constant real not null := 3.14;

foo integer not null := 20;

pi constant real not null := 3.14;

148

The %TYPE Attribute

Declare a variable according to Another previously declared variable.A database column definition.

Prefix %TYPE withThe database table and column.The previously declared variable name.

PL/SQL determines the datatype and size of the variable.

149

The %TYPE Attribute: Examples

Advantages of using the %TYPE attributeThe datatype of the underlying database column may be unknown.The datatype of the underlying database column may change at runtime.

......

v_last_namev_last_name s_emp.last_name%TYPE;s_emp.last_name%TYPE;

v_first_name v_first_name s_emp.first_name%TYPE;s_emp.first_name%TYPE;

v_balancev_balance NUMBER(7,2);NUMBER(7,2);

v_minimum_balancev_minimum_balance v_balance%TYPE := 10;v_balance%TYPE := 10;

......

......

v_last_namev_last_name s_emp.last_name%TYPE;s_emp.last_name%TYPE;

v_first_name v_first_name s_emp.first_name%TYPE;s_emp.first_name%TYPE;

v_balancev_balance NUMBER(7,2);NUMBER(7,2);

v_minimum_balancev_minimum_balance v_balance%TYPE := 10;v_balance%TYPE := 10;

......

150

Variables

Must start with a letter (A-Z)

optionally followed by one or more letters, numbers 0-9, or the special characters $, #, or _

no longer than 30 characters

no spaces embedded in variable name

Cannot use reserved words as variable names

151

Scalar Variable Declarations: Examples

v_gender CHAR(1);

v_total_sal NUMBER(9,2) := 0;

v_order_date DATE := SYSDATE + 7;

c_tax_rate CONSTANT NUMBER(3,2) := 8.25;

v_valid BOOLEAN NOT NULL := TRUE;

v_gender CHAR(1);

v_total_sal NUMBER(9,2) := 0;

v_order_date DATE := SYSDATE + 7;

c_tax_rate CONSTANT NUMBER(3,2) := 8.25;

v_valid BOOLEAN NOT NULL := TRUE;

152

Controlling PL/SQL Flow of ExecutionChange the logical flow of statements by

usingcontrol structures:

Conditional control structures (IF statement)Loop control structures

Basic loopFOR loopWHILE loopEXIT statement

153

If Guidelines

Each if statement followed by its own then

each if statement block terminated by a matching end if

can be one and only one else with every if statement

no matching end if with each elsif

154

The IF Statement: Syntax

You can perform actions selectively based upon conditions being met.

ELSIF is one word.END IF is two words.At most, one ELSE clause is permitted.

IF IF conditioncondition THEN THEN

statementsstatements;;

[ELSIF [ELSIF conditioncondition THEN THEN

statementsstatements;];]

[ELSE[ELSE


END IF;END IF;

IF IF conditioncondition THEN THEN

statementsstatements;;

[ELSIF [ELSIF conditioncondition THEN THEN


[ELSE[ELSE


END IF;END IF;

155

Simple IF Statements: Example

Set the job title to Sales Representative and the region number to 35 if the last name is Dumas.

. . .. . .

IF v_last_name = 'Dumas' THENIF v_last_name = 'Dumas' THEN

v_job := 'Sales Representative'; v_job := 'Sales Representative';

v_region_id := 35;v_region_id := 35;

END IF;END IF;

. . .. . .

. . .. . .

IF v_last_name = 'Dumas' THENIF v_last_name = 'Dumas' THEN

v_job := 'Sales Representative'; v_job := 'Sales Representative';

v_region_id := 35;v_region_id := 35;

END IF;END IF;

. . .. . .

156

IF-THEN-ELSE Statements: ExampleSet a flag for orders where there are fewer than 5 days between order date and ship date.

. . .. . .

IF v_date_shipped - v_date_ordered < 5 THEN IF v_date_shipped - v_date_ordered < 5 THEN

v_ship_flag := 'Acceptable';v_ship_flag := 'Acceptable';

ELSEELSE

v_ship_flag := 'Unacceptable';v_ship_flag := 'Unacceptable';

END IF;END IF;

. . .. . .

. . .. . .

IF v_date_shipped - v_date_ordered < 5 THEN IF v_date_shipped - v_date_ordered < 5 THEN

v_ship_flag := 'Acceptable';v_ship_flag := 'Acceptable';

ELSEELSE

v_ship_flag := 'Unacceptable';v_ship_flag := 'Unacceptable';

END IF;END IF;

. . .. . .

157

IF-THEN-ELSIF Statements: Example

For a given value entered, return a calculated value.

. . .. . .

IF v_start > 100 THENIF v_start > 100 THEN

RETURN (2 * v_start);RETURN (2 * v_start);

ELSIF v_start >= 50 THEN ELSIF v_start >= 50 THEN

RETURN (.5 * v_start);RETURN (.5 * v_start);

ELSEELSE


END IF;END IF;

. . .. . .

. . .. . .

IF v_start > 100 THENIF v_start > 100 THEN

RETURN (2 * v_start);RETURN (2 * v_start);

ELSIF v_start >= 50 THEN ELSIF v_start >= 50 THEN


ELSEELSE


END IF;END IF;

. . .. . .

158

Example

SQL> SET SERVEROUTPUT ON ;SQL> SET SERVEROUTPUT ON ;SQL> SET SERVEROUTPUT ON ;SQL> SET SERVEROUTPUT ON ;

DECLARE DECLARE

v_num NUMBER (2);v_num NUMBER (2);

BEGINBEGIN

v_num := 50;v_num := 50;

DBMS_OUTPUT.PUT_LINE ( ‘Number is ‘ || TO_CHAR (v_num));DBMS_OUTPUT.PUT_LINE ( ‘Number is ‘ || TO_CHAR (v_num));

END;END;

DECLARE DECLARE

v_num NUMBER (2);v_num NUMBER (2);

BEGINBEGIN

v_num := 50;v_num := 50;

DBMS_OUTPUT.PUT_LINE ( ‘Number is ‘ || TO_CHAR (v_num));DBMS_OUTPUT.PUT_LINE ( ‘Number is ‘ || TO_CHAR (v_num));

END;END;

159

Hello World

SET SERVEROUTPUT ON

BEGIN DBMS_OUTPUT.enable; DBMS_OUTPUT.put_line (‘Hello World’);END;/

Will stay on until sessionis completed or it is turnedoff...

SQL*Plus writes out whateverthe server returns to it...

Output mechanism is turnedon. . .

Prints the string. . .

Executes the PL/SQL block

160

Debugging

to see compilation error informationshow errors;

set serveroutput on; -- to enable output from statements below

dbms_output.put_line(expression)Print expression and returns to a new Line

dbms_output.put(expression)Print expression

dbms_output.new_lineNew line

161

Circle Program

SET SERVEROUPUT ONDECLARE PI CONSTANT REAL := 3.14159265359; circumference REAL; area REAL; radius REAL :=&Radius;

BEGIN DBMS_OUTPUT.enable; circumference := PI * 2.0 * radius; area := PI * power(radius,2); DBMS_OUTPUT.put_line(‘Radius = ‘ || TO_CHAR(radius) || ‘, Circumference = ‘ || TO_CHAR(circumference) || ‘, Area = ‘ || TO_CHAR(area));END;/

SET SERVEROUPUT ONDECLARE PI CONSTANT REAL := 3.14159265359; circumference REAL; area REAL; radius REAL :=&Radius;

BEGIN DBMS_OUTPUT.enable; circumference := PI * 2.0 * radius; area := PI * power(radius,2); DBMS_OUTPUT.put_line(‘Radius = ‘ || TO_CHAR(radius) || ‘, Circumference = ‘ || TO_CHAR(circumference) || ‘, Area = ‘ || TO_CHAR(area));END;/

162

LOOP Statements

Loops repeat a statement or sequence of statements multiple times.Three loop types:

Basic loopFOR loopWHILE loop

163

• Iterate through your statements with a basic Iterate through your statements with a basic loop.loop.

• Without the EXIT statement, the loop would be Without the EXIT statement, the loop would be infinite.infinite.

LOOP LOOP

statement1statement1;;

. . .. . .

EXIT [WHEN EXIT [WHEN conditioncondition];];

END LOOP;END LOOP;

LOOP LOOP


. . .. . .

EXIT [WHEN EXIT [WHEN conditioncondition];];

END LOOP;END LOOP;

Basic Loop: Syntax

-- delimiter

-- statements

-- EXIT statement

-- delimiter

164

Basic Loop: Example II

I integer := 0;I integer := 0;

LOOPLOOP

IF (I > 10) thenIF (I > 10) then

EXIT; EXIT; -- “break”-- “break”

END IF;END IF;

I := I + 1;I := I + 1;

END LOOP;END LOOP;

I integer := 0;I integer := 0;

LOOPLOOP

IF (I > 10) thenIF (I > 10) then

EXIT; EXIT; -- “break”-- “break”

END IF;END IF;

I := I + 1;I := I + 1;

END LOOP;END LOOP;

165

Basic Loop: Example I

Insert ten new lines into the table s_item with order number 101

. . .. . .

v_ord_idv_ord_id s_item.ord_id%TYPE := 101;s_item.ord_id%TYPE := 101;

v_counterv_counter NUMBER(2) := 1;NUMBER(2) := 1;

BEGINBEGIN

. . .. . .

LOOPLOOP

INSERT INTO s_item (ord_id, item_id) INSERT INTO s_item (ord_id, item_id)

VALUES (v_ord_id, v_counter);VALUES (v_ord_id, v_counter);

v_counter := v_counter + 1;v_counter := v_counter + 1;

EXIT WHEN v_counter > 10;EXIT WHEN v_counter > 10;

END LOOP;END LOOP;

. . .. . .

. . .. . .



BEGINBEGIN

. . .. . .

LOOPLOOP

INSERT INTO s_item (ord_id, item_id) INSERT INTO s_item (ord_id, item_id)



EXIT WHEN v_counter > 10;EXIT WHEN v_counter > 10;

END LOOP;END LOOP;

. . .. . .

166

FOR Loop: Syntax

Use a FOR loop to shortcut the test for the number of iterations.

Do not declare the index; it is declared implicitly.

FOR FOR indexindex in [REVERSE] in [REVERSE]

lower_bound..upper_boundlower_bound..upper_bound LOOP LOOP



. . .. . .

END LOOP;END LOOP;

FOR FOR indexindex in [REVERSE] in [REVERSE]

lower_bound..upper_boundlower_bound..upper_bound LOOP LOOP



. . .. . .

END LOOP;END LOOP;

167

FOR Loop: Guidelines

Reference the index within the loop only; it is undefined outside the loop.

Use an expression to reference the existing value of an index.

Do not reference the index as the target of an assignment outside the loop

168

For-in-loop-end Loop

DECLAREDECLARE

Temp integer:=0;Temp integer:=0;

Lv integer;Lv integer;

BEGINBEGIN

For cnt in 1 .. 5 loopFor cnt in 1 .. 5 loop Lv := cnt;Lv := cnt; dbms_output.put_line(‘the index: ‘ || to_char(cnt));dbms_output.put_line(‘the index: ‘ || to_char(cnt)); Temp := Temp+1;Temp := Temp+1;end loop;end loop;dbms_output.put_line(‘the last value : ‘ || to_char(Lv));dbms_output.put_line(‘the last value : ‘ || to_char(Lv));Dbms_output.put_line(‘number of iterations :’ || Dbms_output.put_line(‘number of iterations :’ || to_char(temp));to_char(temp));End;End;

DECLAREDECLARE

Temp integer:=0;Temp integer:=0;

Lv integer;Lv integer;

BEGINBEGIN

For cnt in 1 .. 5 loopFor cnt in 1 .. 5 loop Lv := cnt;Lv := cnt; dbms_output.put_line(‘the index: ‘ || to_char(cnt));dbms_output.put_line(‘the index: ‘ || to_char(cnt)); Temp := Temp+1;Temp := Temp+1;end loop;end loop;dbms_output.put_line(‘the last value : ‘ || to_char(Lv));dbms_output.put_line(‘the last value : ‘ || to_char(Lv));Dbms_output.put_line(‘number of iterations :’ || Dbms_output.put_line(‘number of iterations :’ || to_char(temp));to_char(temp));End;End;

ExamplePrint the number of times the loop is executed and the last value for the index.

169

WHILE Loop: Syntax

Use the WHILE loop to repeat statements while a condition is TRUE.

WHILE WHILE conditioncondition LOOP LOOP



. . .. . .

END LOOP;END LOOP;

WHILE WHILE conditioncondition LOOP LOOP



. . .. . .

END LOOP;END LOOP;

Condition isevaluated at the beginning ofeach iteration.

170

WHILE Loop: Example

Insert the first ten new line items for order number 101.

. . .. . .



BEGINBEGIN

. . .. . .

WHILE v_counter <= 10 LOOPWHILE v_counter <= 10 LOOP

INSERT INTO s_item (ord_id, item_id)INSERT INTO s_item (ord_id, item_id)



END LOOP;END LOOP;

. . .. . .

. . .. . .



BEGINBEGIN

. . .. . .

WHILE v_counter <= 10 LOOPWHILE v_counter <= 10 LOOP

INSERT INTO s_item (ord_id, item_id)INSERT INTO s_item (ord_id, item_id)



END LOOP;END LOOP;

. . .. . .

171

Nested Loops and Labels

Nest loops to multiple levels.Use labels to distinguish between blocks and loops.Exit the outer loop with the EXIT statement referencing the label.

172

Nested Loops and Labels: ExampleExit an outer loop based on the values of an

inner block.

......BEGINBEGIN <<Outer-loop>> LOOP<<Outer-loop>> LOOP

v_counter :=v_counter+1;v_counter :=v_counter+1;EXIT WHEN v_counter>10;EXIT WHEN v_counter>10;<<Inner_loop>> LOOP<<Inner_loop>> LOOP

......EXIT Outer_loop WHEN total_done = ‘YES’;EXIT Outer_loop WHEN total_done = ‘YES’;

--Leave both loops--Leave both loops EXIT WHEN inner_done = ‘YES’;EXIT WHEN inner_done = ‘YES’;

--Leave inner loop only--Leave inner loop only ......

END LOOP Inner_loop;END LOOP Inner_loop;......

END LOOP Outer_loop;END LOOP Outer_loop;END; END;

......BEGINBEGIN <<Outer-loop>> LOOP<<Outer-loop>> LOOP

v_counter :=v_counter+1;v_counter :=v_counter+1;EXIT WHEN v_counter>10;EXIT WHEN v_counter>10;<<Inner_loop>> LOOP<<Inner_loop>> LOOP

......EXIT Outer_loop WHEN total_done = ‘YES’;EXIT Outer_loop WHEN total_done = ‘YES’;

--Leave both loops--Leave both loops EXIT WHEN inner_done = ‘YES’;EXIT WHEN inner_done = ‘YES’;

--Leave inner loop only--Leave inner loop only ......

END LOOP Inner_loop;END LOOP Inner_loop;......

END LOOP Outer_loop;END LOOP Outer_loop;END; END;

173

CASE Statement

CASE grade WHEN 'A' THEN dbms_output.put_line('Excellent'); WHEN 'B' THEN dbms_output.put_line('Very Good'); WHEN 'C' THEN dbms_output.put_line('Good'); WHEN 'D' THEN dbms_output.put_line('Fair');WHEN 'F' THEN dbms_output.put_line('Poor');ELSE dbms_output.put_line('No such grade');

END CASE;

174

CASE StatementUsing the following syntax, the CASE statement can evaluate a condition and returns a value for each case:

CASE WHEN shape = 'square' THEN area := side * side;WHEN shape = 'circle' THEN

BEGIN area := pi * (radius * radius);

DBMS_OUTPUT.PUT_LINE('Value is not exact because pi is irrational.'); END;

WHEN shape = 'rectangle' THEN area := length * width; ELSE BEGIN DBMS_OUTPUT.PUT_LINE('No formula to calculate area of a' || shape);

RAISE PROGRAM_ERROR; END; END CASE;

175

Where the parameter syntax isWhere the parameter syntax is

Creating a Procedure: Syntax

PROCEDURE name

[(parameter,...)]

IS

pl/sql_block;

PROCEDURE name

[(parameter,...)]

IS

pl/sql_block;

parameter_nameparameter_name [IN | OUT | IN OUT] [IN | OUT | IN OUT] datatypedatatypeparameter_nameparameter_name [IN | OUT | IN OUT] [IN | OUT | IN OUT] datatypedatatype

176

Creating a Procedure: Guidelines

Use the CREATE OR REPLACE clause when building your procedure in SQL*Plus.

Enter any parameter.

Start the PL/SQL block with IS.

Enter a local variable declaration or the keyword BEGIN after IS.

View procedures and functions:Select text from user_source where name=‘function_or_procedure name’;

177

Procedural Parameter Modes

ProcedureProcedure

(DECLARE)(DECLARE)

BEGINBEGIN

EXCEPTIONEXCEPTION

END;END;

IN Argument

OUT Argument

IN OUT Argument

CallingEnvironment

178

Creating a Procedure: Example

PROCEDURE change_salary

(v_emp_id IN NUMBER,

v_new_salary IN NUMBER)

IS

BEGIN

UPDATE s_emp

SET salary = v_new_salary

WHERE id = v_emp_id;

COMMIT;

END change_salary;

PROCEDURE change_salary

(v_emp_id IN NUMBER,

v_new_salary IN NUMBER)

IS

BEGIN

UPDATE s_emp

SET salary = v_new_salary

WHERE id = v_emp_id;

COMMIT;

END change_salary;

179

Invoking Procedures from Procedure BuilderEnter the procedure name with actual parameters, if applicable, at the Interpreter prompt.

PL/SQL> execute change_salary (17, 1000);PL/SQL> execute change_salary (17, 1000);PL/SQL> execute change_salary (17, 1000);PL/SQL> execute change_salary (17, 1000);

180

Invoking Procedures from Another Procedure: Example

PROCEDURE process_salPROCEDURE process_sal

(v_emp_id IN NUMBER,(v_emp_id IN NUMBER,

v_new_salary IN NUMBER)v_new_salary IN NUMBER)

ISIS

BEGINBEGIN

change_salary (v_emp_id, v_new_salary);change_salary (v_emp_id, v_new_salary);

--invoking procedure change_salary--invoking procedure change_salary

......

END;END;

PROCEDURE process_salPROCEDURE process_sal

(v_emp_id IN NUMBER,(v_emp_id IN NUMBER,

v_new_salary IN NUMBER)v_new_salary IN NUMBER)

ISIS

BEGINBEGIN

change_salary (v_emp_id, v_new_salary);change_salary (v_emp_id, v_new_salary);

--invoking procedure change_salary--invoking procedure change_salary

......

END;END;

181

Creating a Function

Create a PL/SQL function to return a value to the calling environment.

Add a RETURN clause with the datatype in the declaration of the function.

Include at least one RETURN statement in the PL/SQL block.

Use the CREATE OR REPLACE clause when building your FUNCTION in SQL*Plus.

182

Creating a Function: Syntax

FUNCTION FUNCTION namename

[([(parameter,...parameter,...)])]

RETURN RETURN datatypedatatype

ISIS

pl/sql_blockpl/sql_block;;

FUNCTION FUNCTION namename

[([(parameter,...parameter,...)])]

RETURN RETURN datatypedatatype

ISIS

pl/sql_blockpl/sql_block;;

Remember to include at least one RETURN Remember to include at least one RETURN statement in the PL/SQL block.statement in the PL/SQL block.

183

Creating a Function: Example

FUNCTION tax

(v_value IN NUMBER)

RETURN NUMBER

IS

BEGIN

RETURN (v_value * .07);

END;

FUNCTION tax

(v_value IN NUMBER)

RETURN NUMBER

IS

BEGIN

RETURN (v_value * .07);

END;

Return the tax based on the value.Return the tax based on the value.

184

Invoking Functions in SQL Statements

AdvantagesPermit calculations otherwise not easily obtained in SQL.

Increase efficiency of queries.

GuidelinesOnly use stored functions, not procedures.

Single row functions

No DDL statements

Formal parameters must be IN.

185

Calling a Function in a SQL Statement

Valid SQL clausesSelect list of SELECT commandCondition of WHERE and HAVING clauseORDER BY, and GROUP BY clausesVALUES clause of the INSERT commandSET clause of the UPDATE command

186

Invoking Functions in SQL Statements: ExampleEnter a SQL statement with a function call at the Interpreter prompt.

PL/SQL> SELECT total, tax(total)PL/SQL> SELECT total, tax(total)

+> FROM s_ord +> FROM s_ord

+> WHERE id = 100; +> WHERE id = 100;

TOTAL TAX(TOTAL)TOTAL TAX(TOTAL)

------------- ----------------------- ----------

601100.00 42077 601100.00 42077

PL/SQL> SELECT total, tax(total)PL/SQL> SELECT total, tax(total)

+> FROM s_ord +> FROM s_ord

+> WHERE id = 100; +> WHERE id = 100;

TOTAL TAX(TOTAL)TOTAL TAX(TOTAL)

------------- ----------------------- ----------

601100.00 42077 601100.00 42077

187

Retrieving Data: Syntax

Retrieve data from the database with SELECT.

INTO clause is required.Exactly one row must be returned.Full SELECT syntax is available.

SELECTSELECT select_listselect_list

INTOINTO variable_namevariable_name | | record_name record_name

FROMFROM tabletable

WHEREWHERE conditioncondition;;

SELECTSELECT select_listselect_list

INTOINTO variable_namevariable_name | | record_name record_name

FROMFROM tabletable

WHEREWHERE conditioncondition;;

188

Retrieving Data: Example

Retrieve the order date and the ship date for the specified order.

PROCEDURE ship_datePROCEDURE ship_date

(v_ord_id IN NUMBER)(v_ord_id IN NUMBER)

ISIS

v_date_ordered s_ord.date_ordered%TYPE;v_date_ordered s_ord.date_ordered%TYPE;

v_date_shipped s_ord.date_shipped%TYPE; v_date_shipped s_ord.date_shipped%TYPE;

BEGINBEGIN

SELECTSELECT date_ordered, date_shippeddate_ordered, date_shipped

INTOINTO v_date_ordered, v_date_shippedv_date_ordered, v_date_shipped

FROMFROM s_ords_ord

WHEREWHERE id = v_ord_id;id = v_ord_id;

......

END ship_date;END ship_date;

PROCEDURE ship_datePROCEDURE ship_date

(v_ord_id IN NUMBER)(v_ord_id IN NUMBER)

ISIS

v_date_ordered s_ord.date_ordered%TYPE;v_date_ordered s_ord.date_ordered%TYPE;

v_date_shipped s_ord.date_shipped%TYPE; v_date_shipped s_ord.date_shipped%TYPE;

BEGINBEGIN

SELECTSELECT date_ordered, date_shippeddate_ordered, date_shipped

INTOINTO v_date_ordered, v_date_shippedv_date_ordered, v_date_shipped

FROMFROM s_ords_ord


......

END ship_date;END ship_date;

189


Return the sum of the salaries for all employees in the specified department.FUNCTION sum_empFUNCTION sum_emp

(v_dept_id IN NUMBER)(v_dept_id IN NUMBER)

RETURN NUMBERRETURN NUMBER

ISIS

v_sum_salary s_emp.salary%TYPE; v_sum_salary s_emp.salary%TYPE;

BEGINBEGIN

SELECTSELECT SUM(salary) SUM(salary) --group function--group function

INTOINTO v_sum_salaryv_sum_salary

FROMFROM s_emps_emp

WHEREWHERE dept_id = v_dept_id;dept_id = v_dept_id;

RETURN (v_sum_salary);RETURN (v_sum_salary);

END sum_emp;END sum_emp;

FUNCTION sum_empFUNCTION sum_emp


RETURN NUMBERRETURN NUMBER

ISIS

v_sum_salary s_emp.salary%TYPE; v_sum_salary s_emp.salary%TYPE;

BEGINBEGIN

SELECTSELECT SUM(salary) SUM(salary) --group function--group function

INTOINTO v_sum_salaryv_sum_salary

FROMFROM s_emps_emp

WHEREWHERE dept_id = v_dept_id;dept_id = v_dept_id;

RETURN (v_sum_salary);RETURN (v_sum_salary);

END sum_emp;END sum_emp;

190


Retrieve all information about the specified department.

PROCEDURE all_deptPROCEDURE all_dept


ISIS

dept_recorddept_record s_dept%ROWTYPE; s_dept%ROWTYPE;

BEGINBEGIN

SELECTSELECT **

INTOINTO dept_record dept_record --PL/SQL RECORD--PL/SQL RECORD

FROMFROM s_depts_dept

WHEREWHERE id = v_dept_id;id = v_dept_id;

......

END all_dept;END all_dept;

PROCEDURE all_deptPROCEDURE all_dept


ISIS

dept_recorddept_record s_dept%ROWTYPE; s_dept%ROWTYPE;

BEGINBEGIN

SELECTSELECT **

INTOINTO dept_record dept_record --PL/SQL RECORD--PL/SQL RECORD

FROMFROM s_depts_dept

WHEREWHERE id = v_dept_id;id = v_dept_id;

......

END all_dept;END all_dept;

191

Manipulating Data

Make changes to database tables by using DML commands.

INSERTUPDATEDELETE

192

Inserting Data: ExampleAdd a new order to the S_ORD table for the specified customer.PROCEDURE cust_orderPROCEDURE cust_order

(v_customer_id IN s_ord.customer_id%TYPE)(v_customer_id IN s_ord.customer_id%TYPE)

ISIS

v_date_ordered s_ord.date_ordered%TYPE := SYSDATE;v_date_ordered s_ord.date_ordered%TYPE := SYSDATE;

v_sales_rep_id s_ord.sales_rep_id%TYPE := 11;v_sales_rep_id s_ord.sales_rep_id%TYPE := 11;

v_payment_type s_ord.payment_type%TYPE := 'CASH';v_payment_type s_ord.payment_type%TYPE := 'CASH';

v_order_filled s_ord.order_filled%TYPE := 'N';v_order_filled s_ord.order_filled%TYPE := 'N';

BEGINBEGIN

INSERT INTO s_ord (id, customer_id,INSERT INTO s_ord (id, customer_id,

date_ordered, date_shipped, sales_rep_id, date_ordered, date_shipped, sales_rep_id,

total, payment_type, order_filled)total, payment_type, order_filled)

VALUES (s_ord_id.NEXTVAL, v_customer_id, VALUES (s_ord_id.NEXTVAL, v_customer_id,

v_date_ordered, NULL, v_sales_rep_id,v_date_ordered, NULL, v_sales_rep_id,

0, v_payment_type, v_order_filled);0, v_payment_type, v_order_filled);

END cust_order;END cust_order;

PROCEDURE cust_orderPROCEDURE cust_order

(v_customer_id IN s_ord.customer_id%TYPE)(v_customer_id IN s_ord.customer_id%TYPE)

ISIS

v_date_ordered s_ord.date_ordered%TYPE := SYSDATE;v_date_ordered s_ord.date_ordered%TYPE := SYSDATE;

v_sales_rep_id s_ord.sales_rep_id%TYPE := 11;v_sales_rep_id s_ord.sales_rep_id%TYPE := 11;

v_payment_type s_ord.payment_type%TYPE := 'CASH';v_payment_type s_ord.payment_type%TYPE := 'CASH';

v_order_filled s_ord.order_filled%TYPE := 'N';v_order_filled s_ord.order_filled%TYPE := 'N';

BEGINBEGIN

INSERT INTO s_ord (id, customer_id,INSERT INTO s_ord (id, customer_id,

date_ordered, date_shipped, sales_rep_id, date_ordered, date_shipped, sales_rep_id,

total, payment_type, order_filled)total, payment_type, order_filled)

VALUES (s_ord_id.NEXTVAL, v_customer_id, VALUES (s_ord_id.NEXTVAL, v_customer_id,

v_date_ordered, NULL, v_sales_rep_id,v_date_ordered, NULL, v_sales_rep_id,

0, v_payment_type, v_order_filled);0, v_payment_type, v_order_filled);

END cust_order;END cust_order;

193

Updating Data: Example

Change the ship date for the specified order.

PROCEDURE new_ship_datePROCEDURE new_ship_date

(v_ord_id(v_ord_id ININ s_ord.id%TYPE,s_ord.id%TYPE,

v_ship_datev_ship_date IN s_ord.date_shipped%TYPE) IN s_ord.date_shipped%TYPE)

ISIS

BEGINBEGIN

UPDATEUPDATE s_ords_ord

SETSET date_shipped = v_ship_datedate_shipped = v_ship_date


END new_ship_date;END new_ship_date;

PROCEDURE new_ship_datePROCEDURE new_ship_date

(v_ord_id(v_ord_id ININ s_ord.id%TYPE,s_ord.id%TYPE,

v_ship_datev_ship_date IN s_ord.date_shipped%TYPE) IN s_ord.date_shipped%TYPE)

ISIS

BEGINBEGIN

UPDATEUPDATE s_ords_ord

SETSET date_shipped = v_ship_datedate_shipped = v_ship_date


END new_ship_date;END new_ship_date;

194

Deleting Data: Example

Delete a specified order.

PROCEDURE del_orderPROCEDURE del_order

(v_ord_id IN s_ord.id%TYPE) (v_ord_id IN s_ord.id%TYPE)

ISIS

BEGINBEGIN

DELETE FROM s_ordDELETE FROM s_ord

WHERE id = v_ord_id;WHERE id = v_ord_id;

END del_order;END del_order;

PROCEDURE del_orderPROCEDURE del_order

(v_ord_id IN s_ord.id%TYPE) (v_ord_id IN s_ord.id%TYPE)

ISIS

BEGINBEGIN

DELETE FROM s_ordDELETE FROM s_ord

WHERE id = v_ord_id;WHERE id = v_ord_id;

END del_order;END del_order;

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Ch01 Advanced Database mgmt Iyad Zaarour