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Re: distinct clause issue for 600000 records
Posted by: Ra Nala
Date: November 16, 2015 04:12AM

Øystein Grøvlen Wrote:
> Hi,
> I am not sure what "distinct clause issue"

Okay, my question is .... is it good practice to write the DISTINCT in extraction (select query) or not ?. as per my DBA input it is bad practice , his suggestion was, instead of DISTINCT better to write sub select query to avoid duplicates.

> I do not understand what you mean by "Cardinality
> length"

generally when we create foreign key relation ship between master and child tables then be default Cardinality will be created based on 1:1 or 1:n in this way.

as per my DBA input, in my database, large size was created for Cardinality length, and his suggestion is,better to reduce the Cardinality length so that performance will be improved.

I hope you are able to understand the my inputs.

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Re: distinct clause issue for 600000 records
November 16, 2015 04:12AM

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