Why Should You Know Your Data

Today I read one great article on “Improving 2D range query performance" (http://www.sql-server-performance.com/articles/per/2d_range_query_p1.aspx). The article very clearly explained the reasons for the 2 D range query to perform poorly and what you need to do inorder to turn things around. I won’t go into the technical details, but just say that by tweaking the query, the performance changed significantly. You really need to read this article…..

I definitely did gather some very good technical details on the subject, but what struck me most was the assumption that was taken( where an events life time would be no more than 5 days). This assumption made the biggest difference in getting the query performance on the right track.

Question

As technical people do we ask the correct/sufficient questions from the business team? Do we take the time to understand the data in our tables?

Conclusion

As Sql Server people(technical people) we know how to write queries to retrieve data from a table. But by asking the correct question we can make our queries perform lot more efficiently.

Comments

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