Question

我有一个抛出错误的MySQL存储过程。

DELIMITER $$

DROP PROCEDURE IF EXISTS `test_schema`.`TEST_SPROC` $$  
CREATE PROCEDURE `test_schema`.`TEST_SPROC` (IN var0 INT, var1 INT)  
BEGIN

  DECLARE var0 INT;
  DECLARE var1 INT;

  SELECT COUNT(*) INTO var0 FROM INFORMATION_SCHEMA.`TABLES` 
  WHERE `TABLE_SCHEMA`='test_schema' AND `TABLE_NAME`='original_table'; 

  SELECT COUNT(*) INTO var1 FROM INFORMATION_SCHEMA.`COLUMNS` 
  WHERE `TABLE_SCHEMA`='test_schema' AND `TABLE_NAME`='new_table' 
  AND `COLUMN_NAME`='id';

  IF var0=1 THEN
    RENAME TABLE test_schema.original_table TO test_schema.new_table;   
  END IF;

  IF var1=1 THEN
    ALTER TABLE test_schema.new_table CHANGE id AccountID VARCHAR;   

  END IF;       #error is thrown here.

END $$

DELIMITER ;

错误：

脚本行：4您的SQL语法中有错误;检查手册   对应于您的MySQL服务器版本，以获得正确的语法   使用附近';结束如果;
     在第15行
结束'

我的if语句有什么问题？

Answer 1

更改此行：

ALTER TABLE test_schema.new_table CHANGE id AccountID VARCHAR;

到此：

ALTER TABLE test_schema.new_table CHANGE id AccountID VARCHAR(100);

当然，您应该指定适当的VARCHAR列的长度。我刚用VARCHAR(100)作为例子。

Answer 2

您必须为alter table语句指定长度。请参阅以下评论：

IF varTable=1 THEN
    RENAME TABLE test_schema.original_table TO test_schema.new_table;
    SELECT COUNT(*) INTO varColumn FROM INFORMATION_SCHEMA.`COLUMNS` 
    WHERE `TABLE_SCHEMA`='test_schema' AND `TABLE_NAME`='new_table' 
    AND `COLUMN_NAME`='id';

    IF varColumn=1 THEN
      #The following statement must be "VARCHAR(255)"  not just "VARCHAR"
      ALTER TABLE test_schema.new_table CHANGE id AccountID VARCHAR(255);
    ELSE
      #statements.
    END IF;
END IF;

MySQL存储过程错误与IF ... THEN ... END IF;声明

2 个答案: