Delete syntax to delete a record from one table if a matching value isn't found in another

I'm trying to clean up a database design and I'm in a situation to where two tables need a FK but since it didn't exist before there are orphaned records.

Tables are:

Brokers and it's PK is BID

The 2nd table is Broker_Rates which also has a BID table.

I'm trying to figure out a t-sql statement that will parse through all the recrods in the Broker_Rates table and delete the record if there isn't a match for the BID record in the brokers table.

I know this isn't correct syntax but should hopefully clear up what I'm asking

DELETE FROM Broker_Rates

WHERE (Broker_Rates.BID <> Broker.BID)

Thanks

kfrost:

Maybe something like:

DELETE FROM Broker_Rates
from Broker_Rates a
WHERE not exists
( select 0 from Broker b
where a.BID = B.id
)

Dave

|||

That appeared to do the trick. Curious, what does using the 0 in Select 0 person of your string above accomplish. I was using Select *.

Works, just curious for future reference.

Thanks.

|||

I use the zero because the select list is not relevant. Your syntax will work fine. I need to do something like "0 as dummy" so that it is more obvious that the item is a dummy item.

Dave

|||Cool. Thanks!!