Question

我试图在我的数据库上运行商店程序/功能，该程序/功能显示所有具有礼品清单的用户＆lt; 5.我在IF＆＃34;或附近收到错误＆＃34;语法错误。我已单独运行SQL语句，并且工作正常。

--function counts the number of giftlists per user
--and put their names into a new table

CREATE OR REPLACE FUNCTION foo()
  RETURNS TABLE(users_id users.users_id%TYPE, first_name users.first_name%TYPE, last_name      users.last_name%TYPE) AS
$func$
BEGIN

 -- if number of giftlists < 5
 IF(SELECT gift_lists.users_id, COUNT (gift_lists.gift_lists_id) as number_giftlists < 5    FROM gift_lists LEFT  JOIN users ON gift_lists.users_id =
  users.users_id GROUP BY gift_lists.users_id)
  RETURN QUERY
  SELECT v.users_id, v.first_name, v.last_name 
  FROM   my_view v;
ELSE
  RETURN QUERY
  SELECT v.users_id, v.first_name, v.last_name 
  FROM   my_view v;
END IF;
END
$func$  LANGUAGE sql STABLE;

Answer 1

您不能在标准SQL或PostgreSQL的SQL方言中使用顶级IF。

Use CASE .. WHEN ... THEN ... END代替，或使用PL / PgSQL语言。 PL / PgSQL允许您使用IF语句。

另外，这个：

 COUNT (gift_lists.gift_lists_id) as number_giftlists < 5

毫无意义。我想你的意思是：

SELECT
  gift_lists.users_id,
  COUNT (gift_lists.gift_lists_id) as number_giftlists
FROM gift_lists 
  LEFT  JOIN users ON gift_lists.users_id = users.users_id 
GROUP BY gift_lists.users_id
HAVING COUNT (gift_lists.gift_lists_id) < 5

无法执行postgres函数 - IF处的语法错误

1 个答案: