Re: [MonetDB-users] Aggregating by a computed field?

On Wed, Jun 01, 2011 at 12:29:50PM -0700, Synaptic Axon wrote:

On Wed, Jun 1, 2011 at 11:54 AM, Fabian Groffen wrote:

...

On 01-06-2011 11:48:17 -0700, Synaptic Axon wrote:

...

What is the correct way to group by the computed field?  Should I create a view?  Is there a positional syntax for the GROUP BY clause I am overlooking?

Niels knows exactly why this isn't allowed, but why do see this as an issue?  I agree it clobbers the query, but that should be all...

Why do I see it as an issue? I was surprised that it was a syntax error and not supported. I would like to be able to execute aggregate queries against parts of a timestamp, to summarize over various periods of time or any number of other computed columns.

I suppose one method would be to store the year as a separate column but that doesn't seem very flexible. I'm not using MonetDB in production but I'm evaluating it for that purpose. I was just surprised that I could not group by the computed year column and think I must be missing something regarding syntax. This isn't a common use case for you? Aliases should work just fine.

Niels

Thank you.

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