Have you ever tried explaining your job to family or friends and seen their eyes glaze over? Will Thrash explains it better than we did. In the first 15 minutes or so of this video he talks about how he first got interested in data at a young age, and why it still holds his interest to this day. You can tell he gets why we do what we do, and why we all love it. (more…)
A reference for all the different types of keys used in logical and physical database design.
These tables will be used to illustrate all the different keys: (more…)
Viewing execution plans is useful for troubleshooting queries and stored procedures. But sometimes the query or stored procedure takes a long time to run, or you cannot run it yourself because it modifies data.
You can view these plans by pulling them from the plan cache. SQL Server provides a way to do this:
UPDATE 7/18/2016 – When I first wrote this, I thought that this would show the actual execution plans. I have since learned that this shows the estimated execution plans. Hopefully some readers may still find it useful.
Have you ever seen a table where each row had a ‘start date’ and an ‘end date’? I’m sure most of us have seen one or created one.
These tables tend to pose a key problem (no pun intended) if the following business logic applies: “If two or more rows represent different date ranges for a single item, the ranges cannot overlap.” In other words, the date range must be unique from the start date until the end date for any particular item represented by the table. (more…)