Effects of Persisted Columns on Performance

SQL Server 2008, SQL Server 2012, SQL Server 2014, TSQL
I live for questions. And my favorite questions are the ones where I'm not completely sure of the answer. Those are the questions that make me stop presenting in order to take a note so I can try to answer the question later, usually in a blog post. Guess where we are today? I was asked at SQL Bits in LondonĀ about the direct impact of the PERSISTED operator on calculated columns, both inserts and selects. I didn't have a specific answer, so I wrote it down for later (and asked the, self-described, persisting Dane, to email me to remind me. He did, so I put together a few tests to try to answer his question. First, I created three tables: [crayon-5a6d3bcbdc031502630570/] The first table has two calculated columns, one PERSISTED…
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