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From:Rick James Date:October 11 2012 6:40pm
Subject:RE: column aliases in query
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Some places allow aliases, some don't.  Some (GROUP BY, ORDER BY) even allow ordinals.

For performance, the optimal index would be
    INDEX(factory_id, date)
and then do
       WHERE date >= "2012-10-11"
         AND date <  "2012-10-11" + INTERVAL 1 DAY


> -----Original Message-----
> From: Mark Haney [mailto:markh@stripped]
> Sent: Thursday, October 11, 2012 10:47 AM
> To: MySQL
> Subject: column aliases in query
> 
> I know it's been a while since I wrote serious queries, but I'm sure I
> have done something like this before:
> 
> SELECT SUBSTR(date,1,10) as vDate, event_id, events.mach_id,
> machine.factory_id FROM events JOIN machine ON events.mach_id =
> machine.mach_id WHERE machine.factory_id = "1" AND vDate = "2012-10-11"
> 
> Where I've aliased the SUBSTR of the date and then used the alias in
> the WHERE clause of the query.  I'm getting an error message now, but
> I'm almost certain I've used that syntax before.  Am I missing
> something?
> 
> --
> 
> Mark Haney
> Software Developer/Consultant
> AB Emblem
> markh@stripped
> Linux marius.homelinux.org 3.5.1-1.fc17.x86_64 GNU/Linux
> 
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Thread
column aliases in queryMark Haney11 Oct
  • RE: column aliases in queryRick James11 Oct
  • Re: column aliases in queryhsv11 Oct