Question

在MYSQL存储过程中，我需要选择两个表列，和将列选择为变量，以便在该过程中进一步使用。

下面是存储过程的简化版本。

DECLARE pUSR_ID BIGINT;
DECLARE pPRJ_ID BIGINT;
DECLARE pUSR_LAN_ID BIGINT;

SELECT USR_ID, USR_Login, USR_Password, USR_Archived, USR_Deleted, 
  USR_ID, USR_PRJ_ID, USR_LAN_ID INTO pUSR_ID, pPRJ_ID, pUSR_LAN_ID
FROM tblUsers
WHERE USR_Login = 'foobar';

当我执行上面的存储过程时，我收到以下错误信息，这是有道理的。

Error Code: 1222. The used SELECT statements have a different number of columns

因此，我将变量放在第一位，将其他列放在变量之后。

SELECT USR_ID, USR_PRJ_ID, USR_LAN_ID INTO pUSR_ID, pPRJ_ID, pUSR_LAN_ID,
  USR_ID, USR_Login, USR_Password, USR_FullName, USR_IsProjectAdmin, USR_Archived,
  USR_Deleted

执行此操作将返回：Error 1327: Undeclared variable: USR_ID。我理解为什么会收到错误。

我不明白的是我如何选择表格列和在同一个语句中选择某些列到变量中？

Answer 1

/*
DECLARE pUSR_ID BIGINT;
DECLARE pPRJ_ID BIGINT;
DECLARE pUSR_LAN_ID BIGINT;
*/ /*no need to declare*/


SELECT 
@pUSR_ID:=USR_ID, 
USR_Login, 
USR_Password, 
USR_Archived, 
USR_Deleted, 
USR_ID, 
@pPRJ_ID:=USR_PRJ_ID, 
@pUSR_LAN_ID:=USR_LAN_ID 
FROM tblUsers
WHERE USR_Login = 'foobar';

选择列到变量以及其他列

1 个答案: