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Codage, syntaxe et commandes
>>Is there a way to combine SEEK with SELECT (or a better way) to select records EXCEPT for those referenced in another table?
>>
>>I have two tables:
>>
>>The main table contains all records indexed by an ID field.
>>
>>The second table contains the IDs of records from the first table that have already been processed, also indexed by the ID field.
>>
>>I wish to select all records from the first table EXCEPT those for which the ID is listed in the second table.
>>
>>It would seem that a statement such as this should work:
>>
>>
>>SELECT (fieldnames);
>> FROM main_table;
>> WHERE (search criteria);
>> AND NOT SEEK(done_table.id);
>> into cursor c_results
>>
>>
>>I'm obviously overlooking something....
>>
>>All assistance appreciated!
>>
>>Thanks,
>>
>>Neil Preston
>You need a nested subquery...
>select id from table1 where id not in(select id from table2)
>HTH
If the second table is large, for speed you could try
select id from table1 left join table2 on table1.id = table2.id where isnull(table2.id)
Cheers
Steve Lea
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