Re: Self-Referencing

On Thursday, 29. March 2001 01:38, David Olbersen wrote:
[snip]
>   SELECT
>     building_id,
>     num_buildings,
>     (
>       SELECT count( building_id )
>       FROM   building_portals
>       WHERE  building_id = THIS.building_id
>     )
>   FROM buildings;

Try this query (untested), using table aliases:

SELECT b.building_id, b.num_buildings,  ( SELECT count( bp.building_id )     FROM building_portals bp    WHERE
bp.building_id= b.building_id ) FROM buildings b;
 

You could also write <table>.<field> instead.

Hope that helps.

Christof
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