How to set the default transaction isolation level server wide?

Last week I was involved in a discussion about the default transaction isolation level used by the transaction objects in WCF’s services (Serializable) versus the one used by the transaction objects in Entity Framework for SQL Server (ReadCommitted) whose details I’m not going to cover in this post.   At a given point during that…


Even if some client tools in SQL seem to be forward compatible with later versions, you may be missing something important

Today, a colleague exposed the following case:   In the execution plan I do see some exclamatory marks on Sort, Hash Joins operators but there is no warning information available. I am using SQL Server 2012.  How do I interpret the exclamatory marks?       Here goes my explanation to this problem: New execution…


Does larger TEMPDB log file affect the performance of startup of SQL Server?

I invested some time today investigating what SQL Server does with the initialization of TEMPDB’s log file, because a question was raised last week during Robert Davis session on TEMPDB at SQL PASS Summit in Seattle, and I wasn’t sure about what the answer would be. The reason why people is afraid the size of…


Are you one of those rare birds whom, while running batches that involve distributed queries, have encountered any of the following errors?

3988 – New transaction is not allowed because there are other threads running in the session. 3930 – The current transaction cannot be committed and cannot support operations that write to the log file. Roll back the transaction.   If so, I would appreciate you send me an email to telling me your story….