MySQL DELETE Query
If you want to delete a record from any MySQL table, then you can use SQL command DELETE FROM. You can use this command at mysql> prompt as well as in any script like PHP.
Syntax:
Here is generic SQL syntax of DELETE command to delete data from a MySQL table:
DELETE FROM table_name [WHERE Clause]
If WHERE clause is not specified, then all the records will be deleted from the given MySQL table.
You can specify any condition using WHERE clause.
You can delete records in a single table at a time.
The WHERE clause is very useful when you want to delete selected rows in a table.
Deleting Data from Command Prompt:
This will use SQL DELETE command with WHERE clause to delete selected data into MySQL table tutorials_tbl.
Example:
Following example will delete a record intotutorial_tbl whose tutorial_id is 3.
root@host# mysql -u root -p password;
Enter password:*******
mysql> use TUTORIALS;
Database changed
mysql> DELETE FROM tutorials_tbl WHEREtutorial_id=3;
Query OK, 1 row affected (0.23 sec)
mysql>
Deleting Data Using PHP Script:
You can use SQL DELETE command with or without WHERE CLAUSE into PHP functionmysql_query(). This function will execute SQL command in similar way it is executed at mysql> prompt.
Example:
Try out the following example to delete a record from tutorial_tbl whose tutorial_id is 3.
<?php
$dbhost = 'localhost:3036';
$dbuser = 'root';
$dbpass = 'rootpassword';
$conn = mysql_connect($dbhost, $dbuser, $dbpass);
if(! $conn )
{
die('Could not connect: ' .mysql_error());
}
$sql = 'DELETE FROM tutorials_tbl
WHERE tutorial_id=3';
mysql_select_db('TUTORIALS');
$retval = mysql_query( $sql, $conn );
if(! $retval )
{
die('Could not delete data: ' .mysql_error());
}
echo "Deleted data successfully\n";
mysql_close($conn);
?>
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