You have to understand that a foreign key in a table is actually a so-called "constraint". In other words it limits the content of that field to something that already exists in the table the foreign key refers to. It does not automatically retrieve that corresponding info for you. You will have to do that yourself through your query.

One possible SQL statement is: 

SELECT detail_tbl.detail, user_tbl.name, topic_tbl.topic
FROM detail_tbl, user_tbl, topic_tbl
WHERE detail_tbl.name_id = user_tbl.id
AND detail_tbl.topic_id = topic_tbl.id

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There are some modules that make handling foreign key fields somewhat easier. You may wish to have a look at DBIx::Class and more specifically DBIx::Class::Relationship that handles many-to-many relationships (which is what you are trying to do).

CountZero

A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James

My blog: Imperial Deltronics

In reply to Re: Retrieving data from db with foreign keys by CountZero
in thread Retrieving data from db with foreign keys by acondor

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