SQL Server Performance Forum – Threads Archive
Normalize a non-normalized DB
Hello, I got DBs from a client which have their tables populated but it was not normalized during its initial design stages. The databases are in ACCESS and SQL-Server and I want them normalized in their respective applications (i.e. access and sqlserver). Everytime I try to initiate the relationship links and enforce referential integrity, I get error messages prohibiting this. Can anyone tell me an easy and effecient way I can do this without losing the data contained in the tables?Can you tell us what is the error message that you got
Apparently the existing data is not only unnormalized, but it probably also contains duplicate keys and unmatched foreign keys.<br /><br />Unfortunately you can’t fix a major problem like this in an easy and efficient way – it must be done properly. The client probably thought they’d found an "easy and efficient" way to create a database – yeah right
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Yes, this is no trivial task. And usually it’s a labour-intensive task.
If you want to do it properly, you first create a new logical and physical model, create the application and migrate the data. Just by moving to SQL Server, clicking on some buttons and – voila – have a normalized schema, would be too good to be true. Your client should be aware that you would almost start anew, if you’re doing it right. —
Frank Kalis
Microsoft SQL Server MVP
http://www.insidesql.de
Ich unterstütze PASS Deutschland e.V. http://www.sqlpass.de)
Yeah even I am doing that and I have created a new database and trying to migrate all the data into my new database,I hope there is no other easy way. Its really a labour-intensive as Frank said. Thanks!
"He laughs best who laughs last"
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