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DISJOIN in MySQL

hi folks,

Need some help. Am new to SQL and have to run a query on two tables A
and B to extract some data. Here, B is a subset of A for the field
that's common to both of them. How can we get only those rows that
belong to A but not to B, that is, all rows in (table A - table B) on
the basis of that common field?

Thanks in advance,

Raj

Jul 27 '05 #1
2 4040
SELECT stuff from table1 a LEFT JOIN table2 b ON a.key1=b.key2 WHERE
b.something is NULL;
<ra******@gmail .com> wrote in message
news:11******** *************@g 14g2000cwa.goog legroups.com...
hi folks,

Need some help. Am new to SQL and have to run a query on two tables A
and B to extract some data. Here, B is a subset of A for the field
that's common to both of them. How can we get only those rows that
belong to A but not to B, that is, all rows in (table A - table B) on
the basis of that common field?

Thanks in advance,

Raj

Jul 28 '05 #2
hi NewbGuy, thanks for the reply. This query doesn't seem to be correct
as it will result in a table with 0 rows since the condition
"b.somethin g is NULL" will return 0.

Jul 28 '05 #3

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