Insert & Update while Locking tables

Question

Update & Insert
Is it possible for me to insert a record and update 2 fields in another record, whil locking the database tables for the process to take place?
If so, how?
Thanks
Pete

Answer 1

I don't know which database server you are using. But in MySQL, you can do something like this:
<?php
function get_next_number( $field = 'id' )
     $id = 0;
     //Lock the table for write
     mysql_query('LOCK TABLES name_of_table WRITE');
     $sql = 'SELECT '.$field.' FROM name_of_table ORDER BY '.$field.' DESC LIMIT 1';
     $query = mysql_query($sql);
     if ( mysql_num_rows($query) > 0 )
          $row = mysql_fetch_row($query);
          //Get the $field value
          $id = $row[0];
     //Unlock tables
     mysql_query('UNLOCK TABLES');
     return ++$id;
?>
I didn't test this function, but the idea is that
Check if you are connected to MySQL server
Regards,
Rafael