// Loads adodb mysql.inc.php for mysql

ADOLoadCode( mysql );

// Loads adodb db2.inc.php for db2

ADOLoadCode( db2 );

Connecting to database

ADOdb uses an object oriented approach to manage the complexity of 

handling multiple databases. This is done by passing an input parameter for 

the database driver name while creating the connection object. The 

connection instance for DB2 can be created using 

ADONewConnection( db2 )

or 

NewADOConnection( db2 )

.

After creating the connection instance, you need to connect to the database 

using:

  PConnect()

It creates a persistent connection, which is faster because this connection 

is never closed.

  Connect()

It creates a non persistent connection, which takes up much fewer 

resources though, therefore reducing the risk of your database and your 

Web server becoming overloaded. 

  NConnect()

It forces the creation of a new connection. 

Example 7 31 and Example 7 32 show the changes in connection code in the 

ADOdb PHP program. All the above connect methods take four parameters 

(systemname, username, password, databasename) in MySQL, whereas in 

DB2 UDB ODBC, it only requires three parameters (dbname, username, 

password). Also, we can set the cursor mode to 

SQL_CUR_USE_ODBC 

for 

optimization purposes

.

Example 7 31   MySQL creating connection in ADOdb

// create connection instance for MySQL

$db = &ADONewConnection( mysql ); 

$db >Connect( localhost ,  itso ,  itso ,  itsodb ); 

Example 7 32   DB2 creating connection in ADOdb

// create connection instance for DB2 UDB

$conn = &ADONewConnection( db2 ); 

$conn >curMode = SQL_CUR_USE_ODBC;

$conn >Connect( itsodb2 , itso , itso );

184 

MySQL to DB2 UDB Conversion Guide