Create variables in MySQL stored procedure with DECLARE keyword

Use MySQL DECLARE for variables in stored procedure −

DECLARE anyVariableName int DEFAULT anyValue;

Let us implement the above syntax in order to create variables in stored procedure −

mysql> DELIMITER //
mysql> CREATE PROCEDURE variable_Demo()
    -> BEGIN
    -> DECLARE lastInsertedId int DEFAULT -1;
    -> select lastInsertedId;
    -> set @providedLastId=10001;
    -> select @providedLastId;
    -> END
    -> //
Query OK, 0 rows affected (0.32 sec)
mysql> DELIMITER ;

Now you can call the above stored procedure using CALL command −

mysql> call variable_Demo();

This will produce the following output −

+----------------+
| lastInsertedId |
+----------------+
|             -1 |
+----------------+
1 row in set (0.00 sec)

+-----------------+
| @providedLastId |
+-----------------+
|           10001 |
+-----------------+
1 row in set (0.02 sec)
Query OK, 0 rows affected (0.04 sec)