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Thread: Are piped columns indexable

Are piped columns indexable

From
"Mark Steben"
Date:

Hi all,

Just upgraded to 8.2.5. 

 

Given table t with columns a, b, c, d

  And index on t using btree (a,b)

   Is this indexable:

  Select * from t where a || b = ‘124cab’  (or whatever)

    Assume a and b are defined as char(3)

 

I have tried various op classes and so far have just gotten sequential scans

 

Thanks for your time

 

 

Mark Steben

Senior Database Administrator
@utoRevenue™
A Dominion Enterprises Company
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Re: Are piped columns indexable

From
"Merlin Moncure"
Date:
On Wed, Mar 12, 2008 at 4:38 PM, Mark Steben <msteben@autorevenue.com> wrote:
> Given table t with columns a, b, c, d
>
>   And index on t using btree (a,b)
>
>    Is this indexable:
>
>   Select * from t where a || b = '124cab'  (or whatever)
>
>     Assume a and b are defined as char(3)
> I have tried various op classes and so far have just gotten sequential scans


create index t_idx on t((a || b));

:-)

merlin