Hi, I'm a novice.
I've designed a database that supports many to many relationships (actually
many to many to many) and I need help creating the query to find my data. I
know things like JOINs exist, but don't have a clue how to use them.
I have three main tables and two link tables, The main tables are A, B, and C.
Each are defined with id INT and word VARCHAR(32); The link tables are X and Y.
X links A and B with the columns a_id and b_id. Y links the tables B and C with
columns b_id and c_id.
Here's what I want to accomplish:
Get the A.id where A.word = "some value"
Use A.id to search X where X.a_id=A.id (from above)
Use all occurences of X.a_id = A.id to select word from B using B.id=X.b_id
AND finally,
select C.id where C.Word = "Some other value"
and given Y.c_id = C.id use the matching Y.b_id to further limit the select
on B.word
Can this convoluted mess be understood and if so, can a single query pull it
off?
I'm implementing this in perl, so I can break the queries into pieces if I
absolutely have to.
Thanks
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