Is this query bad.....?

[Hum Dum]

Select Min(Priority) from Outbox where [Transmitted] = false and [FolderId] IN (7,8) and
[Deleted] = false and [InterfaceNo] =@InterfaceNo and [SwitchingAddressNo] NOT IN
(Select [SwitchingAddressNo] from AddressBook where [Block] = true and [Deleted] = false

The above query i wrote, and its working fine. I want to know the performance related issues with this? If its ugly? then how can i improve the same.

[PSK_]

You are using NOT IN in you query, it is not good for the query performance as the query is not going to use benefits of indexes defined on the table and will use a sequential scan on the entire table, try to use NOT EXISTS.

WWW, WCF, WWF, WPF, WFC .... WTF

[programmervb netc]

Does this apply to all DBs? I have never used NOT EXISTS...

Humble Programmer

[Don Burton]

Indexes and Index Hints - possibly.

[PSK_]

I am sure about SQL Server, Oracle and Sybase but no idea about other DB servers.

WWW, WCF, WWF, WPF, WFC .... WTF