Re: delete based on multipart key
In article <334330B8.4D64@gte.net>, Douglas Wilson <dgwilson@gte.net> wrote:
>David Williams wrote:
>(snip)
>> delete from first_table
>> where 1 in
>> (select 1 from first_table,second_table
>> where first_table.a = second_table.a and
>> first_table.b = second_table.b)>>
>(snip)
>> Somehow though I still don't feel I totally understand WHY it works...
>
I don't understand it either, David, but it still does a SEQUENTIAL SCAN
of first_table.
Why? Absolutely no clue.
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Rudy Fernandes
GIC, Kuwait
OL 7.20UC4, 4GL 6.04UC1
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