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Foreign key problem

From: <frebe73_at_gmail.com>
Date: 12 Jun 2006 22:19:16 -0700
Message-ID: <1150175956.098492.15000@i40g2000cwc.googlegroups.com>


I am working on an application which need a data model that reflects the schema structure. My tables are ("*" indicates primary key column):

tableinfo(*table_name)
columninfo(*table_name, *col_name)
fk(*fk_name, pk_table, fk_table)
fk_column(*fk_name, *fk_column, pk_column)

My problem is the last table, fk_column. How can I define a foreign key for fk_column.fk_column (and pk_column) referencing the table columninfo? The column table_name is not an member of the table fk_column, but it could easily be joined from the fk table, but I don't think that helps me with defining the foreign key constraint?

The corresponding information_schema tables in MySQL looks like this (simplified):
table_constraints(*constraint_name, table_name) key_column_usage(*contraint_name, *table_name, *column_name, referenced_table_name, referenced_column_name)

In this case it is possible to define foreign key constraints, but I don't consider these tables normalized. The value of table_name is given by the constraint_name and should not be repeated in the second table.

Somebody that have a pice of advice?

Fredrik Bertilsson Received on Tue Jun 13 2006 - 00:19:16 CDT

Original text of this message

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