MySQL结合两个查询

问题描述：

我有两个MySQL查询

I have two MySQL queries

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

他们给我1栏.我想执行交叉连接并仅返回两个选择查询中都存在的值.有可能吗?

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 ?

答

如何

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

在FROM子句中使用子查询时，就像在创建临时表一样. 然后使用别名可以引用它们并执行INNER JOIN

When you use subqueries in a FROM clause, it's like if you are making temporary tables. Then with the alias you can refer to them and do a INNER JOIN

MySQL结合两个查询

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