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    DB2 SQL - DML (Data Manipulation Language) - Part II

    Different Types of SELECTS

    SELECT *

    SELECT COLUMN(s)

    SELECT DISTINCTSELECT .. WHERESELECT ... WHERE... AND / OR

    SELECT ... WHERE... LIKESELECT ... WHERE... IN

    BETWEEN Operator

    Let us assume we have following tables defined on our database.

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    SORT * FROM

    Select all records from DEPARTMENT table

    SQL Query : SELECT * FROM DEPARTMENT

    Result :

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    SORT COLUMN NAME FROM

    Get all Department names from the table.

    SQL Query : SELECT DEPTNAME FROM DEPARTMENT

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    SELECT DISTINCT

    Get distinct departments from EMPLOYEE table.

    SQL Query : SELECT DISTINCT DEPT FROM EMPLOYEE

    Result :DEPT

    A00D01

    SELECT ... WHERE ...

    Get the all the employees working in department number A00

    SQL Query : SELECT * FROM EMPLOYEE WHERE DEPT = 'A00'

    Result :

    Following row wont get displayed since this employee belong to DEPT D01

    1006 MIKE DWAYER 1001 D01 15000 2002-07-19

    Following Relational Operators we can use in WHERE clause

    The WHERE clause

    is used to specify that only certain rows of the table are displayed, based on

    the criteria described in that WHERE clause.

    SELECT ... WHERE ... Complex Comditions

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    The AND operator joins two or more conditions, and displays a row only if that row's data

    satisfies ALL conditions listed For example, to display all staff making over $15,000, andbelong to department no A00 use:

    SQL Query :

    SELECT EMPNAMEFROM EMPLOYEE

    WHERE SALARY > 15000 AND DEPT = 'A00'

    Result :

    The OR operator joins two or more conditions, but returns a row if ANY of the conditions

    listed hold true.

    SELECT ... WHERE ... LIKE - NOT LIKE

    Get all employee details whoes names starts with M.

    SQL Query : SELECT * FROM DEPT FROM EMPLOYEE WHERE EMPNAME LIKE 'M%'Result :

    The percent sign (%) is used to represent any possible character (number, letter, orpunctuation) or set of characters that might appear after the "M". To find those people with

    Name's ending in "M", use '%M', or if you wanted the "M" in the middle of the word, try'%M%'. The '%' can be used for any characters in the same position relative to the given

    characters. NOT LIKE displays rows not fitting the given description.

    NOTE : The wild-card characters for LIKE are '%' and '_'.Underscore matches any single character. Percent matches zero or more characters.

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    SELECT ... WHERE ... IN

    When want to compare list of values compare against the table field you can use IN.

    Get all employee details for employee numbers 1001, 1003 and 1005

    SQL Query :

    SELECT EMPNAME FROM EMPLOYEEWHERE EMPNO IN ( 1001, 1003 and 1005 )

    Result :

    SELECT ... WHERE ... BETWEEN

    You can use BETWEEN Operator , to get the range of records between two values.

    SYNTAX : Field [NOT] BETWEEN Value-1 AND Value-2

    Get all employee details who is getting salary between 15000 and 40000 ( including theseamounts)

    SQL Query :

    SELECT EMPNO, EMPNAME FROM EMPOYEE

    WHERE SALARY BETWEEN 15000 AND 40000

    Result :

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    SELECT ... WHERE ... IS [NOT] NULL

    We need to use this operator when we want to get the record which contains NULLS.

    Get all Records who does not have managers assinged.

    SQL Query :

    SELECT EMPNO, EMPNAME FROM EMPLOYEE

    WHERE MGRNO IS NULL

    Result :

    SQL / DB2 UNIVERSAL DATABASE / DB2 DATABASE / SQL / DB2 / DB2 DATABASE / SQL /

    DB2 / DB2 DATABASE