In my previous article I showed how read committed would allow rows to be updated that it had already processed in a query, because it releases locks as soon as it has processed that row or page (depending upon the type of lock taken). A second query using the same criteria would then show different …
In a previous article I demonstrated how use of READUNCOMMITTED (or the NOLOCK hint) can result in erroneous data, due to page splits. Examples abound of the more common issue with this isolation level, which occur when reading a row that is being updated in another transaction and then rolled back. These so-called ‘dirty reads’ …
Having prepared the Distributor in the previous article it is now possible to create a Subscription. First of all create a test database and table on the Publisher (Publisher-A): A database is also required on the Subscriber (Subscriber-C): Now back to the Publisher. This server needs to be configured as a Publisher. The steps used …
A couple of questions recently in SQL Server Central have related to Snapshot Backups and reminded me of an article I wrote a few years ago about such things for the Developers in my office. So, using that as a basis for this article I’m going to explain the basics of Snapshot Backups. In the …
Seriously, you shouldn’t get excited about a function, command or whatever. It’s just a tool for a job and not the reason you live. But then in SQL 2005 Row_Number was introduced. I didn’t do a great deal of work with SQL 2000 but I do remember the fun to be had when trying to …
Notes on SQL 