Make a usable Join relationship with LINQ on top of a database CSV design error

Posted by jdk on Stack Overflow See other posts from Stack Overflow or by jdk
Published on 2010-05-11T15:07:56Z Indexed on 2010/05/11 15:24 UTC
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Filed under:

linq-to-sql

|

c#

|

sql-server

I'm looking for a way to fix and/or abstract away a comma-separated values (CSV) list in a database field in order to reconstruct a usable relationship such that I can properly join the two tables below and query them using LINQ and its Join method.

Following is a sample showing the Person table and CsvArticleIds field having a CSV value to represent a one-to-many association with Article records.

TABLE [dbo].[Person]

Id Name       CsvArticleIds
-- ---------- --------
1  Joe        "15,22"
5  Ed         "22"
10 Arnie      "8,15,22"

^^^(Of course a link table should have been created; nonetheless the relationship with articles is trapped inside that list of CSV values.)

TABLE [dbo].[Article]

Id Title
-- ----------
8  Beginning C#
15 A Historic look at Programming in the 90s
22 Gardening in January

Additional Info

the fix can be at any level: C#.NET or SQL Server
something easy because I will be repeating the solution for many other CSV values in other tables.
Elegant is nice too.
not looking for efficiency because this is part of a one-time data migration task and can take as long as it wants to run.

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