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copy old column's values to new column
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* copy old column's values to new column
@ 2004-09-02 13:16  ogjunk-pgjedan@yahoo.com
  0 siblings, 1 reply; 2+ messages in thread

From: ogjunk-pgjedan@yahoo.com @ 2004-09-02 13:16 UTC (permalink / raw)
  To: pgsql-sql

Hello,

I need some basic SQL help.  I added a new column to an existing table,
and now I need to copy values from one of the old columns to this new
columns.

I need something like this:

FOR pvId IN SELECT id FROM preference_value LOOP
        update preference_value SET display_value = (select value from
preference_value where id=pvId) where id=pvId;
END LOOP;

I tried running this from psql, but it didn't work (I suspect FOR can
be used in functions, which I don't know how to write in PG, yet).

Is there a simple way to do this?

Thanks,
Otis




^ permalink  raw  reply  [nested|flat] 2+ messages in thread

* Re: copy old column's values to new column
@ 2004-09-02 13:51  Bruno Wolff III <bruno@wolff.to>
  parent: ogjunk-pgjedan@yahoo.com
  0 siblings, 0 replies; 2+ messages in thread

From: Bruno Wolff III @ 2004-09-02 13:51 UTC (permalink / raw)
  To: ogjunk-pgjedan@yahoo.com; +Cc: pgsql-sql

On Thu, Sep 02, 2004 at 06:16:47 -0700,
  ogjunk-pgjedan@yahoo.com wrote:
> Hello,
> 
> I need some basic SQL help.  I added a new column to an existing table,
> and now I need to copy values from one of the old columns to this new
> columns.
> 
> I need something like this:
> 
> FOR pvId IN SELECT id FROM preference_value LOOP
>         update preference_value SET display_value = (select value from
> preference_value where id=pvId) where id=pvId;
> END LOOP;
> 
> I tried running this from psql, but it didn't work (I suspect FOR can
> be used in functions, which I don't know how to write in PG, yet).
> 
> Is there a simple way to do this?

Assuming you are just copying "value" to "display_value", can't you just do:


UPDATE preference_value SET display_value = value;



^ permalink  raw  reply  [nested|flat] 2+ messages in thread

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