Syntax
------ 
{DEALLOCATE | DROP} PREPARE stmt_name
 
Description
----------- 
To deallocate a prepared statement produced with PREPARE,
use a
DEALLOCATE PREPARE statement that refers to the prepared
statement
name.
 
A prepared statement is implicitly deallocated when a new
PREPARE command is issued. In that case, there is no need to
use DEALLOCATE.
 
Attempting to execute a prepared statement after
deallocating it
results in an error, as if it was not prepared at all:
 
ERROR 1243 (HY000): Unknown prepared statement handler
(stmt_name) given to EXECUTE
 
If the specified statement has not been PREPAREd, an error
similar to the following will be produced:
 
ERROR 1243 (HY000): Unknown prepared statement handler
(stmt_name) given to DEALLOCATE PREPARE
 
Example
 
See example in PREPARE.
 


URL:
https://mariadb.com/kb/en/deallocate-drop-prepared-statement/