I have worked with every version of SQL Server since it was first available from Microsoft on OS/2. Each version has improved the features, the stability, and the scalability, and I've looked forward to each change. In many of the companies I worked at, we had a fairly homogenous environment, with one or two versions to support. I think some of that was the timing of my employment dates with the version release dates. If I'd stayed longer at a few jobs, I think I might have ended up supporting three versions of SQL Server in a few places.

That seems to have changed, however with the long delay of SQL Server 2005, and then the very short delays for SQL Server 2008 and 2008 R2. Now it seems many companies have two or three versions at a minimum and might have 4 versions, with SQL Server 2000 servers still available. The last year on Twitter I've seen a number of DBAs noting that they are retiring SQL Server 2000 instances at a good clip, with a few people eliminating the version from their environments, but there are plenty of instances still out there.

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