Sams Teach Yourself PHP in 24 Hours, Third Edition

Changing Data

You can change data using the mysql_query() function in conjunction with an UPDATE statement.

A successful UPDATE statement does not necessarily change any rows. You need to use a function to call mysql_affected_rows() to discover whether you have changed data in your table. mysql_affected_rows() optionally accepts a link resource; if this is missing, the most recent connection is assumed. This function can be used with any SQL query that can alter data in a table row.

Listing 13.6 builds a script that enables an administrator to change any of the values in the domain column of our sample table.

Listing 13.6. Using mysql_query() to Alter Rows in a Database

1: <?php 2: $user = "p24_user"; 3: $pass = "cwaffie"; 4: $db = "p24"; 5: ...