Re: views: performance implication

John Moore wrote:
> We hope to use views as a way to give customers odbc based ad-hoc query 
> access to our database while enforcing security. The reason is that we do 
> not want to put data into separate tables by customer, but rather use a 
> customer ID as part of any query criteria on any table.
> 
> So the question is: are there any negative performance implications of 
> doing so (other than the obvious of having more data in a table than is of 
> interest to the querying customer)? Back in the old days, views were a 
> performance no-no in Informix, so I want to be sure we aren't setting a big 
> trap for ourselves.

Views are rewritten as rules for every query issued, so there is little
performance impact except for the complexity of your view (GROUP BY,
aggregates, etc.)

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