Last week I blogged about Implicit Conversions that cause Index Scans, and showed two charts for where implicit conversions could result in an index scan operation instead of an index seek during query execution.  As a part of writing that blog post I thought it would be interesting to also look at the performance overhead of the column-side implicit conversion occurring, given that I’ve seen it’s effects a number of times in the last few weeks.  Today my article How expensive are column-side Implicit Conversions? went live on the SQLPerformance.com site to show using Performance Monitor information on CPU usage and batch requests per second, the effect of the performance overhead when column-side implicit conversions occur that cause index scans during query execution.