Implicit Conversions as a Performance Problem

Implicit Conversions as a Performance Problem

In SSMS in a query window put a query you wish to analyse. You can either choose to display an estimated execution plan or the actual execution plan.  You can highlight the query and right click for the option or use the menu.

Execution Plan:
Look for a Yellow Triangle on the first Icon. It looks like a Yield Sign with an Exclamation point (!). this means that the query engine is doing an implicit Conversion. This is a problem since it often means that it will ignore a useful Index. This is an easy fix it that you can make the Conversion Explicit and it will run faster and use the Index. But you need to figure out what collum is being converted.

Graphical Execution Plan Icons 

(SQL Server Management Studio)
https://technet.microsoft.com/en-us/library/ms175913(v=sql.105).aspx