Question

我有两张桌子： datess，deletess，sample

我写了一个这样的查询：

DELETE FROM sample
WHERE sample_date_key IN
(SELECT date_key FROM datess WHERE s_date BETWEEN '2015-02-18' and DATE'2015-02-25');

但我在deletess中有2行和2列：

start_date  |  end_date
------------+----------
2015-02-18  | 2015-02-18
2015-01-18  | 2015-01-18

我想删除sample中start_date和end_date之间deletess之间日期的所有行。

我尝试了以下代码，但收到了错误：

错误：用作表达式
的子查询返回多行

(SELECT date_key FROM datess WHERE s_date BETWEEN (SELECT start_date FROM deletess) AND (SELECT end_date FROM deletess);

我感谢任何帮助。谢谢！

Answer 1

您可以使用WHERE EXISTS来检查是否有任何符合条件的行：

DELETE FROM sample
WHERE sample_date_key IN
(
  SELECT date_key
  FROM datess 
  WHERE EXISTS (
    SELECT 1
    FROM deletess
    WHERE s_date BETWEEN start_date
                     AND end_date
  )
);

Answer 2

join优于in

DELETE s
FROM sample s
INNER JOIN datess d
    ON s.sample_date_key = d.date_key
INNER JOIN deletess sd
    ON sd.start_date <= d.s_date
       AND d.s_date <= sd.end_date;

查询从表中删除行

2 个答案: