MySQL - UPDATE Query MYSQL

You can do so by using the SQL UPDATE command to modify any field value of any MySQL table.

Syntax

The following code block has a generic SQL syntax of the UPDATE command to modify the data in the MySQL table −

UPDATE table_name SET field1 = new-value1, field2 = new-value2
[WHERE Clause]

• You can update one or more fields altogether.
• You can specify any condition using the WHERE clause.
• You can update the values in a single table at a time.

The WHERE clause is very useful when you want to update the selected rows in a table.

You can use the SQL UPDATE command with or without the WHERE CLAUSE into the PHP function – mysql_query(). This function will execute the SQL command in a similar way it is executed at the mysql> prompt.

Example

The following example to update the tutorial_title field for a record having tutorial_id as 3.

<?php
   $dbhost = 'localhost:3036';
   $dbuser = 'root';
   $dbpass = 'rootpassword';
   $conn = mysql_connect($dbhost, $dbuser, $dbpass);
   
   if(! $conn ) {
      die('Could not connect: ' . mysql_error());
   }

   $sql = 'UPDATE tutorials_tbl
      SET tutorial_title="Learning JAVA"
      WHERE tutorial_id=3';

   mysql_select_db('TUTORIALS');
   $retval = mysql_query( $sql, $conn );
   
   if(! $retval ) {
      die('Could not update data: ' . mysql_error());
   }
   echo "Updated data successfully\n";
   mysql_close($conn);
?>