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Unanswered: Many-to-Many Query Help
I have a classical many-to-many DB design: Contractors_table, Trades_table, Contract_Trades.
I am looking to run a query that will return what trades this contractor does not do.
Any help will be greatly appreciated.
"trades this contractor does not do" --
FROM Trades_table AS t
JOIN Contract_Trades AS ct
ON ct.trade_id = t.id
AND ct.contractor_id = 937
WHERE ct.contractor_id IS NULL
if u have small data then try with not in r not exists also queries
according to performance exists will have more performance than in
i think so............
Thank you r937 that worked perfectly.