DROP PROCEDURE IF EXISTS add_att_batch_id;  
DELIMITER // #将“；”转意
CREATE PROCEDURE add_att_batch_id() 
BEGIN
  DECLARE CurrentDatabase VARCHAR (100) ;
  SELECT 
    DATABASE() INTO CurrentDatabase ; #获得当前数据库名称
  IF NOT EXISTS 
  (SELECT 
    * 
  FROM
    information_schema.columns 
  WHERE table_schema = CurrentDatabase 
    AND table_name = 'test' 
    AND column_name = 'attbatch_id') 
  THEN ALTER TABLE test 
    ADD COLUMN `attbatch_id` VARCHAR (36) COMMENT '附件批ID' ;
  END IF ;
END //
DELIMITER ; #结束转意
CALL add_att_batch_id();
DROP PROCEDURE IF EXISTS add_att_batch_id;