mysql - 从子查询中选择 "the best result"？

Question

SELECT * FROM table1
WHERE col1 = ANY (
    SELECT DISTINCT col2 FROM table2
    WHERE first = 'blah'
    OR second = 'blahblah'
    OR third = 'blahblahblah' );

子查询检查三列(first、second、third)。在此示例中，我使用 ANY，但我希望它像这样返回:

If found `first` return `first`
else if found `second` return `second`
else if found `third` return `third`

知道我在说什么吗？我只能选择优先级为 first、second、third

的 1 行(最好的)

Answer 1

我想你想要这个:

SELECT * FROM table1
WHERE col1 = (
    SELECT col2 FROM table2
    WHERE first = 'blah'
    OR second = 'blahblah'
    OR third = 'blahblahblah'
    ORDER BY
    first = 'blah' DESC,
    second = 'blahblah' DESC,
    third = 'blahblahblah' DESC
    LIMIT 1
);