12

2 つの MySQL クエリがあります

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

彼らは私に1列を与えます。クロス結合を実行して、両方の選択クエリに存在する値のみを返したいと思います。それは可能ですか?

4

1 に答える 1

31

どうですか

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

句でサブクエリを使用するとFROM、一時テーブルを作成するようなものになります。次に、エイリアスを使用してそれらを参照し、INNER JOIN

于 2012-11-15T15:33:05.330 に答える