mysql使用存储过程

CREATE PROCEDURE <过程名> ( [过程参数[,…] ] ) <过程体>
[过程参数[,…] ] 格式
[ IN | OUT | INOUT ] <参数名> <类型>

drop procedure if exists procedureName;
delimiter //
create procedure procedureName BEGIN
IF NOT EXISTS(SELECT * FROM information_schema.columns WHERE column_name = columnName AND
TABLE_SCHEMA = databaseName AND table_name = tableName)
THEN
ALTER TABLE tableName ADD COLUMN department_id varchar(255) DEFAULT NULL COMMENT columnName;
END IF;
END;
//
delimiter ;
call procedureName;
drop procedure if exists procedureName;