Jan 302010
Prepare statement in MySQL
Answer:
MySQL 5.1 provides support for server-side prepared statements, allow you to code more efficient database driven program.
Example:
mysql> PREPARE stmt_password FROM 'SELECT password(?)';
Query OK, 0 rows affected (0.00 sec)
Statement prepared
mysql> SET @a = 1;
Query OK, 0 rows affected (0.00 sec)
mysql> EXECUTE stmt_password USING @a;
+-------------------------------------------+
| password(?) |
+-------------------------------------------+
| *E6CC90B878B948C35E92B003C792C46C58C4AF40 |
+-------------------------------------------+
1 row in set (0.00 sec)
mysql> SET @a = 2;
Query OK, 0 rows affected (0.00 sec)
mysql> EXECUTE stmt_password USING @a;
+-------------------------------------------+
| password(?) |
+-------------------------------------------+
| *12033B78389744F3F39AC4CE4CCFCAD6960D8EA0 |
+-------------------------------------------+
1 row in set (0.00 sec)
As you can see above, once you have prepared the statement in server, you can reuse the statement by injecting a new value. It is faster since MySQL only need to one time SQL statement parsing, rather than parse your SQL statement every time and execute.