July 2011 - Posts

• Entering TRY blocks is not free, but still several times cheaper than catching exceptions.

  The overhead of entering a TRY block is relatively small, but the overhead of catching an exception is more substantial. If we manage to use CASE or IF to prevent an exception, we can noticeably improve performance. We shall run benchmarks and see for Read More... Posted Tuesday, July 26, 2011 11:15 AM by Alexander Kuznetsov | 9 Comments Filed under: T-SQL Programming, Refactoring, T-SQL Performance

• Comparing the cost of INSERT ... EXEC and its alternatives

  It is well known that INSERT ... EXEC is not free, but how expensive is it as compared to its alternatives? We shall run benchmarks and see that: Invoking a multi-statement UDF is approximately two times faster than capturing the output of a stored procedure Read More... Posted Monday, July 25, 2011 8:15 PM by Alexander Kuznetsov | 3 Comments

• A free book entitled "Version Control by Example" by Eric Sink is available for download

  I have just downloaded and started reading a free PDF book about version control systems (VCS), entitled Version Control by Example , written by Eric Sink. So far I have read a really informative chapter about the advantages of third generation VCS, such Read More... Posted Sunday, July 24, 2011 9:30 PM by Alexander Kuznetsov | 1 Comments Filed under: Source Control, VCS, version control

• More specific queries may run faster, but we should not overdo it.

  It is well known that replacing a generic, one-size-fits-all query with several more specific ones may boost performance. However, in some cases these more specific queries do not perform any faster than the generic one. We shall consider several examples Read More... Posted Wednesday, July 20, 2011 11:01 PM by Alexander Kuznetsov | 0 Comments Filed under: T-SQL Programming, Refactoring

• Will wrapping up code in a reusable stored procedure hurt performance?

  In T-SQL programming, stored procedure calls are not free, and nested stored procedure calls cost even more. First, we shall prove it by running benchmarks. Next, we shall determine if the cost of calling stored procedures is high as compared to the rest Read More... Posted Wednesday, July 20, 2011 2:03 PM by Alexander Kuznetsov | 6 Comments Filed under: T-SQL Programming, Refactoring