Oracle Db• Using SQL*Plus to Interact with Oracle

– User student accounts :S12344567 (Sstudentno)• Password: ‘student’

– setenv ORACLE_HOME /usr/local/oracle8i/product/8.1.6

– setenv LD_LIBRARY_PATH /usr/lib:$ORACLE_HOME/lib

– set path=($path $ORACLE_HOME/bin)– Connection to cse2030 DB:

$sqlplus S1234567/student@cse2030

SQL> (‘prompt’)

SQLPlus• CREATE TABLE Emp(EmpID NUMBER,

Name VARCHAR2(30), PRIMARY KEY (EmpID));

• INSERT INTO Emp VALUES(1, 'Alan Turing');

• Another way is to use substitution variables. INSERT INTO Emp VALUES(&id, '&name');– You will be prompted to enter a value for id,

type in 2 and hit enter. Next you will be prompted to enter a value for name, type in Samual Morse and hit enter

SQLplus cont.• To repeat the command without re-typing it,

type the slash character ( / ) and then hit enter.

• Your tables should have a primary key and Foreign key for referential integrity in one-to-many relationships. EG Authors & Book

• Select * from emp;– To retrieve all data

Primary keys by Ashley Cambrell

– CREATE TABLE test1(testid NUMBER CONSTRAINT pk_test1_testid PRIMARY KEY, testtext VARCHAR(255));

– CREATE SEQUENCE testid_seq INCREMENT BY 1;

– SELECT testid_seq.nextval FROM DUAL;NEXTVAL

------- 1

1 row selected (0.00 seconds)

– SELECT testid_seq.currval FROM DUAL;CURRVAL

-------

1

1 row selected (0.00 seconds)

Primary Key’s cont.– CREATE TABLE test1(testid NUMBER

CONSTRAINT pk_test1_testid PRIMARY KEY, testtext VARCHAR(255));

– INSERT INTO test1(testid, testtext) VALUES(testid_seq.nextval, 'The lazy dog jumped over the brown fox');

– SELECT * FROM test1;

TESTID TESTTEXT

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

2 The lazy dog jumped over the brown fox

1 row selected (1.00 second)

Primary Key’s cont.– INSERT INTO test1(testid, testtext)

VALUES(testid_seq.nextval, 'The lazy fox jumped over the purple dog');

– SELECT * FROM test1;

TESTID TESTTEXT

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

2 The lazy dog jumped over the brown fox

3 The lazy fox jumped over the purple dog

2 rows selected (0.00 seconds)

OCIPLogon• OCIPLogon -- Connect to an Oracle database and

log on using a persistent connection. Returns a new session.– int OCIPLogon ( string username, string password [,

string db])

• CIPLogon() creates a persistent connection to an Oracle 8 database and logs on. The optional third parameter can either contain the name of the local Oracle instance or the name of the entry in tnsnames.ora to which you want to connect. If the optional third parameter is not specified, PHP uses the environment variables ORACLE_SID (Oracle instance) or TWO_TASK (tnsnames.ora) to determine which database to connect to.

OCILogOff• OCILogOff -- Disconnects from Oracle

– int OCILogOff ( int connection)

• PHP oracle function documentation at http://www.php.net/manual/en/function.ociplogon.php

OCIParse• OCIParse -- Parse a query and return a

statement– int OCIParse ( int conn, string query)

• OCIParse() parses the query using conn. It returns the statement identity if the query is valid, FALSE if not. The query can be any valid SQL statement or PL/SQL block.

• Don't forget that the queries on PHP DON'T use the semicolon at the end of the SQL command.Putting a semicollon at the end will give a "Invalid Character" error.

OCIExecute• OCIExecute -- Execute a statement

– int OCIExecute ( int statement [, int mode])

OCIExecute() executes a previously parsed statement. (see OCIParse()). The optional mode allows you to specify the execution-mode (default is OCI_COMMIT_ON_SUCCESS). If you don't want statements to be committed automatically specify OCI_DEFAULT as your mode.

• Returns TRUE on success, FALSE on failure.

OCIError• OCIError -- Return the last error of stmt|conn|

global. If no error happened returns FALSE. – array OCIError ( [int stmt|conn|global])

• OCIError() returns the last error found. If the optional stmt|conn|global is not provided, the last error encountered is returned. If no error is found, OCIError() returns FALSE. OCIError() returns the error as an associative array. In this array, code consists the oracle error code and message the oracle errorstring.

OCIError eg.$c = ocilogon("u","p");

if (! $c) var_dump(ocierror()); // we have no connection yet

// so the error is stored global. $s = ociparse($c,"select * from tubu");

if (! $s) var_dump(ocierror($c)); // parse failed - error is

// stored in connection handle

$err = ociexecute($s);

if ( !$err) var_dump(ocierror($s)); // error code for ociexecute() // is stored in the statement handle

OCIFetchInto• OCIFetchInto -- Fetches the next row into

result-array (can be ‘generic’ without using column names)– int OCIFetchInto ( int stmt, array & result [, int mode])

• OCIFetchInto() fetches the next row (for SELECT statements) into the result array. OCIFetchInto() will overwrite the previous content of result. By default result will contain a zero-based array of all columns that are not NULL. The mode parameter allows you to change the default behaviour.

OCIFetch• OCIFetch -- Fetches the next row into

result-buffer– int OCIFetch ( int statement)

• OCIFetch() fetches the next row (for SELECT statements) into the internal result-buffer.

• Used with OCIResult() to return individual columns.

OCIResult• OCIResult -- Returns column value for

fetched row– mixed OCIResult ( int statement, mixed column)

• OCIResult() will return everything as strings except for abstract types (ROWIDs, LOBs and FILEs). – NOTE: OCIResult() requires the column name to

be written in capitals, so OCIResult($stmt,"column") won't work, but OCIResult($stmt,"COLUMN") will.

PHP / Oracle Example<HTML> <HEAD> <TITLE>Using PHP to Read a Table in Oracle </TITLE>

</HEAD> <BODY BGCOLOR="#FFFFFF">

<CENTER><B>Authors</B> <BR><BR> <?php

$DB_USERNAME='jceddia';$DB_PASSWORD='jpasswd';$DB_DATABASE='cse2030';

$connection = ocilogon($DB_USERNAME, $DB_PASSWORD, $DB_DATABASE);

$stmt = OCIParse($connection, "SELECT * FROM author");

OCIExecute($stmt);

PHP / Oracle Example cont.// Start of table and column headings (ID and Name) print "<TABLE CELLSPACING=\"0\" CELLPADDING=\"3\" BORDER=\"1\">\n"; print " <TR><TH>AID</TH><TH>Firstname</TH><TH>Surname</TH></TR>\n";

// Loop through results while(OCIFetch($stmt)) { print " <TR>\n"; print " <TD>" . OCIResult($stmt, "AID") . "</TD>\n"; print " <TD>" . OCIResult($stmt, "FNAME") . "</TD>\n"; print " <TD>" . OCIResult($stmt, "SNAME") . "</TD>\n"; print " </TR>\n"; } print "</TABLE>\n";

OCIFreeStatement($stmt); OCILogoff($connection); ?>

Putting it all together• It refers to HTML form, php and Oracle

• Two ‘scenarios’– a. “Input scenario”

• form input is to be added/deleted/lookup/etc to database eg. User login, add customer details etc

– b. “Output scenario”• database contents is to be displayed on the form eg.

Once user logs in, display a welcome message with their name from the database or display a product list in the selection box etc

Input Scenario• Define your HTML form to capture the data

you want (to be stored in the db).• Design your php script to be called from the

‘form submit’ to do initial input validation (eg. Name not blank). If input OK, connect to database and insert/amend data.

• EG. See p-6-2.html for the form (calls)– p-6-2.php This would validate data as per the

lab plus connect to db and issue an insert statement using the ‘sequence’ for the primary key and the form variables as the insert VALUES

Input Scenario eg.• Form has two variables ‘name’ and ‘occupation’• Database has table ‘occupation’ with attributes

PersonId,Oname, Ooccupation and personseq as the sequence to use for PK’s

• Insert statement (after connection):$sqlstr = “INSERT INTO occupation(Personid, Oname,

Ooccupation) VALUES(personseq.nextval, “. $name.”,”.$occupation.”);”

$stmt = OCIParse($connection, $sqlstr");

OCIExecute($stmt);

// $err = ociexecute($s);

//if ( !$err) var_dump(ocierror($s));

Output Scenario• Earlier example showed listing the table

contents as a HTML table.• If you want to display data in a drop down

list box then change the HTMLecho “<select name="cars">”while(OCIFetch($stmt)) { echo " <option >”. OCIResult($stmt, “CARMAKE") .”\n";

} echo "</select>\n"; • For a textfield, the VALUE would be set to OCIResult(…)

etc

Design Considerations• Database should be specified first according

to functionality

• HTML forms designed to fulfil part of functionality

• Navigation flow of forms

• Graphic content/CSS added