When is IGNORE_DUP_KEY = ON useful? Jacob Sebastian and I built an example that shows its transactional behavior when you insert only nonduplicate rows.
SQL SERVER – Difference Temp Table and Table Variable – Effect of Transaction
Temp table versus table variable, part two: a transaction rollback undoes changes to a temp table, but a table variable keeps its values.
SQL SERVER – Interesting Observation of DMV of Active Transactions and DMV of Current Transactions
sys.dm_tran_active_transactions and sys.dm_tran_current_transaction look alike, but one lists active transactions for the instance, the other only your session.
SQL SERVER – Transaction and Local Variables – Swap Variables – Update All At Once Concept
Two ideas with examples: transactions have no effect on local variables, and an UPDATE applies all its changes at once, which lets you Swap Variables in one go.
SQL SERVER – Detailed Explanation of Transaction Lock, Lock Type, Avoid Locks
How do you find which table has a transaction lock and what lock type it is? Imran Mohammed explains it for SQL Server 2000 and 2005, and how to avoid locks.
SQL SERVER – 2005 -Track Down Active Transactions Using T-SQL
Want to track down active transactions in your database? One simple DMV query on sys.dm_tran_session_transactions returns them in SQL Server 2005.
SQL SERVER – Two Connections Related Global Variables Explained – @@CONNECTIONS and @@MAX_CONNECTIONS
@@CONNECTIONS and @@MAX_CONNECTIONS explained: login attempts since SQL Server started versus the most simultaneous user connections allowed.