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Re: count() question
Posted by: Craig Matthews
Date: March 30, 2005 03:54AM

James, just to understand covering indexes, in your second SQL, the columns being selected are "organization" and "count(*)"

My understanding of covering index, which may be wrong, is that it includes an index on all the columns referenced in an SQL statement.

So the covering index would include:

- organization
- client id
- paid

Is this incorrect? (Also I am guessing that the "count(*)" would just pick up one of the fields from the index)

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March 24, 2005 08:01PM
March 28, 2005 08:42PM
Re: count() question
March 30, 2005 03:54AM


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