MYSQL PL/SQL
A set of SQL statements with high speed. Only the first execution needs to go through compilation and optimization steps, and the subsequent calls can be executed directly.
Sample:
DROP PROCEDURE IF EXISTS `proc_ adder`
DELIMITER & &
CREATE DEFINER= `root` @ `localhost` PROCEDURE `proc_ adder` (IN an int, IN b int, OUT sum int)
BEGIN
DECLARE c int
/ * DECLARE c int DEFAULT 10 minutes /
If an is null then set a = 0
End if
If b is null then set b = 0
End if
Set sum = a + b
END
& &
DELIMITER
Description:
DEFINER: creator
DECLARE: defining variabl
SET: assign to a variable
SELECT... The INTO statement assigns values to variables as follows:
SELECT col_name [,...] INTO var_name [,...]
FROM table_name WEHRE condition
DELIMITER:
The default statement Terminator in MySQL is the semicolon (;). The SQL statement in the stored procedure requires a semicolon (;) to end. To avoid conflicts, first set the MySQL Terminator to & & with "DELIMITER & &". Finally, use "DELIMITER;" to restore the Terminator to a semicolon. This is the same as when you create a trigger.
Common syntax:
IF:
IF type = 0 THEN
Set c = 'param is 0'
ELSEIF type = 1 THEN
Set c = 'param is 1'
ELSE
Set c = 'param is others, not 0 or 1'
END IF
CASE:
CASE type
WHEN 0 THEN
Set c = 'param is 0'
WHEN 1 THEN
Set c = 'param is 1'
ELSE
Set c = 'param is others, not 0 or 1'
END CASE
WHILE:
DECLARE i int
DECLARE s int
SET I = 0
SET s = 0
WHILE i
