data-konzept

'Earlier I wrote a blog post about how to remove leading and trailing spaces with TRIM function. SQL SERVER – 2017 – How to Remove Leading and Trailing Spaces with TRIM Function? After writing this blog post lots of people asked me its impact on the performance of SQL Server.

Previously I had written similar blog posts, you can read them before reading this blog post further:

• SQL SERVER – TRIM Function to Remove Leading and Trailing Spaces of String – SQL in Sixty Seconds #040 – Video

• SQL SERVER – 2008 – Enhanced TRIM() Function – Remove Trailing Spaces, Leading Spaces, White Space, Tabs, Carriage Returns, Line Feeds

• SQL SERVER – 2008 – TRIM() Function – User-Defined Function

• SQL SERVER – TRIM() Function – UDF TRIM()

Previously we have seen that whenever we use any function on the column used in WHERE condition, the performance is degraded. Most of the time when we use a function on the WHERE clause SQL Server have to apply that function to the entire column before the where a condition is evaluated. This is the reason, we usually do not see seek on the column. When SQL Server has to apply a function on an entire column of SQL Server, it has to scan the column which is usually (most of the time, but not always) expensive than seeking operation.'...

https://blog.sqlauthority.com/2018/01/17/sql-server-performance-observation-trim-function/