[nycphp-talk] input..select help
Scott Mattocks
crisscott at netzero.com
Mon May 10 13:00:47 EDT 2004
Rahmin Pavlovic wrote:
> insert into table_b(field1,field2) select table_a.field1, table_a.field2 from table_a
>
> Which worked fairly quickly, however it also imported entries from table_a that already exist in table_b.
> So I'm wondering if someone could help me figure out how to just grab the new entries from table_a.
Try something like this:
INSERT INTO table_b (field1, field2)
(SELECT table_a.field1, table_a.field2
FROM table_a
LEFT JOIN table_b
ON (table_a.field1 = table_b.field1
AND
table_a.field2 = table_b.field2)
WHERE table_b.field1 IS NULL
AND table_b.field2 IS NULL)
I would try the select first to make sure that it will get you
everything in table_a that isn't already in table_b. And then if you
like the results from that add the insert part to the begining.
Scott Mattocks
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