sql - how would i get it to show me records in one table that arent present in another table using an EQUI JOIN? -
select c.customerno, name, telephone, address, postcode customer c, carforsale s not (c.customerno=s.customerno);
so i'm meant produce output shows customers not have record in car sale table. thought of putting in not in clause essentialy bring ones arent there it's bringing whole table back.
a simple rule: never use commas in from
clause. actually, there slight modification ms access, because not support cross join
. so, use commas when intend cross join
.
you cannot want inner join
. can use left join
, still equi-join:
select c.customerno, name, telephone, address, postcode customer c left join carforsale s on c.customerno = s.customerno s.customerno null;
a left join
keeps rows in first table, when on
clause not true. where
clause chooses rows have no match.
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