Re: To De-Normalize or Normalize ?

One trick I've picked up which sort of fits your post is that when writing client-server (for me this is forms4.5 on V7.x) I don't denormalise the data as such but I do soemtimes denormalise the foreign keys.

i.e. Table TAB1 has column EMP_ID which is a foreign key on to EMP.

Rather than use TAB1 as a base table for a block in a form create a view which has the join done to denormalise it giving the emplyee details as part of the view.

In doing this, the join is still performed at query time but is performed on the server rather than the work being done on the client (in a POST-QUERY trigger) easing network traffic. You can then also query on the employee details without the need for PRE-QUERY work then as well.

Don't know if this helps.

Generally though I'd certainly consider denormalising data if the join to fetch it is heavy duty and performed often. i.e if the join from TAB1 to EMP above to get the employee name was through three or four intermediate tables.

Basically though, you have to take each instance of denormalisation on it;s own merits.

--
Alan D. Mills


Christian Roig wrote in message <360a208f.11106841_at_news.tele.dk>...


>How do you get faster response-times from queries ?

>

>Some people argue that you

>

>A)

>have to De-Normalize your database, so that you have fewer joins, which in

 turn


>results in faster response-times from your queries.

>

>B)

>have to Normalize your database, so that you can have more data in memory,

 which


>in turn results in faster response-times from your queries.

>

>

>What is YOUR experience ?

>

>Why and/or When do YOU either De-Normalize or Normalize your database ?

>

>TIA - Christian

>

>

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