MySQL MySQL结合两个查询
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MySQL combine two queries
提问by litenull
I have two MySQL queries
我有两个 MySQL 查询
QUERY:
SELECT sodnik_1 FROM prihodnji_krog WHERE file_id='8778' AND sodnik_1 != ''
UNION
SELECT sodnik_2 FROM prihodnji_krog WHERE file_id='8778' AND sodnik_2 != ''
UNION
SELECT sodnik_3 FROM prihodnji_krog WHERE file_id='8778' AND sodnik_3 != ''
UNION
SELECT sodnik_4 FROM prihodnji_krog WHERE file_id='8778' AND sodnik_4 != ''
QUERY:
SELECT value FROM notification_sodniki WHERE user_id='16'
OUTPUT LOOKS LIKE THIS:
Name 1
Name 2
Name 3
Name 4
IN BOTH TABLES
They give me 1 column. I'd like to perform a cross join and return only the values that are present in both select queries. Is that possible ?
他们给了我 1 列。我想执行交叉联接并仅返回两个选择查询中都存在的值。那可能吗 ？
回答by Marc
How about
怎么样
SELECT * FROM
(
SELECT sodnik_1 as value FROM prihodnji_krog WHERE file_id='8778' AND sodnik_1 != ''
UNION
SELECT sodnik_2 as value FROM prihodnji_krog WHERE file_id='8778' AND sodnik_2 != ''
UNION
SELECT sodnik_3 as value FROM prihodnji_krog WHERE file_id='8778' AND sodnik_3 != ''
UNION
SELECT sodnik_4 as value FROM prihodnji_krog WHERE file_id='8778' AND sodnik_4 != ''
) x INNER JOIN
(
SELECT value FROM notification_sodniki WHERE user_id='16'
) y
ON x.value = y.value
When you use subqueries in a FROMclause, it's like if you are making temporary tables.
Then with the alias you can refer to them and do a INNER JOIN
当您在FROM子句中使用子查询时，就像您在制作临时表一样。然后使用别名，您可以参考它们并执行INNER JOIN
