I am trying to figure out how to have two "IN" statements.
I'm trying to get something like this, although I don't know how to use both of the nested select statements.
$query_row=mysql_query(
"SELECT DISTINCT * FROM table_a WHERE field_1 IN
(SELECT field_1 FROM table_b WHERE field_2 = $field_2),
(SELECT field_3 FROM table_c WHERE field_4 = $fi开发者_StackOverflow中文版eld_4)
ORDER BY field_5 DESC
");
If I remove one of the (SELECT...
bits, it works, but trying to put them both does not.
Table a has matching values in tables B and C: fields 2 and 4 respectively.
How do I get this to work?
Depending if you want to test if IN either or both:
WHERE field_1 IN (SELECT field_1 FROM table_b WHERE field_2 = $field_2) AND/OR field_1 IN (SELECT field_3 FROM table_c WHERE field_4 = $field_4) ...
You could try it with a UNION:
SELECT DISTINCT *
FROM table_a
WHERE field_1 IN (SELECT field_1 FROM table_b WHERE field_2 = $field_2
UNION
SELECT field_3 FROM table_c WHERE field_4 = $field_4)
ORDER BY field_5 DESC
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