Top vs. Max

T-SQL
The company I work for has a very well defined need for versioned data. In a lot of instances, we don't do updates, we do inserts. That means that you have to have mechanisms for storing the data that enables you to pull out the latest version of all the data or a particular version of all the data, or the data at a particular moment in time, regardless of version.  That means maintaining a version table and a series of inserts into various tables. Some tables will have pretty much a new row for each version, some tables may only have one or two versions out of a chain. With the help of a very smart Microsoft consultant, Bill Sulcius, we have a mechanism that works very well. However,…
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Presentation Last Week

Misc, SQL Server, T-SQL
Last week I presented at the Southern New England SQL Server User Group (SNESSUG) where I'm the Program Director. I presented from the book, Dissecting Execution Plans, that is supposed to be published any day now. I kept it basic and it flowed very well. The audience seemed receptive and there were a few questions. Mostly around figuring out what to do when you saw certain problems within the execution plans. Since that was the goal of the presentation, I was ready for most of the questions. I got stumped once on a Constant Scan operation. I finally looked it up this morning and feel silly. Here's the query: INSERT INTO [AdventureWorks].[Person].[Address]      ([AddressLine1]      ,[AddressLine2]      ,[City]      ,[StateProvinceId]      ,[PostalCode]      ,[rowguid]      ,[ModifiedDate] VALUES ('1313 Mockingbird Lane'…
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