MariaDB update query

The UPDATE command modifies an existing field by changing the value. I t uses the SET clause to specify the column to modify and to specify the new value assigned. T hese values can be expressions or default values for a field. T he DEFAULT keyword is required to set the default value. T he command can also use the WHERE clause to specify the conditions and/or ORDER BY clauses for updates in a specific order.

See the following general syntax -

UPDATE table_name SET field=new_value, field2=new_value2,...
[WHERE ...]

Execute the UPDATE command from a command prompt or using a PHP script.

Command prompt

At the command prompt, simply use the standard commandroot -

root@host# mysql -u root -p password;
Enter password:*******
mysql> use PRODUCTS;
Database changed
mysql> UPDATE products_tbl
   SET nomenclature = 'Fiber Blaster 300Z'
      WHERE ID_number = 112;
mysql> SELECT * from products_tbl WHERE ID_number='112';
+-------------+---------------------+----------------------+
| ID_number   | Nomenclature        | product_manufacturer |
+-------------+---------------------+----------------------+
| 112         | Fiber Blaster 300Z  | XYZ Corp             |
+-------------+---------------------+----------------------+      

PHP update query script

Use the mysql_query() function in UPDATE command statements -

<?php
   $dbhost = ‘localhost:3036’;
   $dbuser = ‘root’;
   $dbpass = ‘rootpassword’;
   $conn = mysql_connect($dbhost, $dbuser, $dbpass);

   if(! $conn ) {
      die(‘Could not connect: ‘ . mysql_error());
   }

   $sql = ‘UPDATE products_tbl
      SET product_name = ”Fiber Blaster 300z”
      WHERE product_id = 112’;

   mysql_select_db(‘PRODUCTS’);
   $retval = mysql_query( $sql, $conn );

   if(! $retval ) {
      die(‘Could not update data: ‘ . mysql_error());
   }

   echo “Updated data successfully
”;
   mysql_close($conn);
?>

After a successful data update, you will see the following output -

mysql> Updated data successfully