Re: select where multiple joined records match
Robin Hughes <[email protected]>
| Newsgroups | gmane.comp.db.mysql.perl |
|---|---|
| Message-ID | <[email protected]> |
You need to first do a self join on the table to get
one table identifying RESOURCE_IDs that meet your
criteria:
ID RESOURCE_ID GRADE SUBJECT
1 1 1 English
2 1 1 Soc
3 1 2 English
4 2 1 English
5 2 3 Soc
6 3 2 English
7 4 1 English
create temporary table tmp as
select G1.RESOURCE_ID
from goals G1 inner join goals G2 on
G1.RESOURCE_ID = G2.RESOURCE_ID
and G1.SUBJECT = G2.SUBJECT
and
where
GR1.GRADE = 1
and GR2.GRADE = 2;
THEN:
select *
from tmp inner join goals g on
tmp.resource_id = g.resource_id
where g.GRADE in (1, 2);
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