I am working on reading execution plans for several stored procedures in a database. While looking at one, I see that the first item on the rightmost section of the execution plan has 80% of the load of the execution plan. The Properties of this node indicate the following:
CONVERT_IMPLICIT(VARCHAR(12),[Database_Name].[dbo].[Table_Name].[Column_Name]as[C.ColumnName], 0) LIKE @InputParameter
This is then followed by an output list. The Input Parameter is of VARCHAR data type, and the column it is comparing to is of is part of a composite key and is of data type INT. I think the difference in data types between these 2 may be causing this CONVERT_IMPLICIT line but I am unsure. What is the cause of this line, and what can I do to remedy it so that the index that is being used can be used properly and use an index seek instead of an index scan which is what is currently happening?