data-konzept

'Indexes are a vast subject and well documented elsewhere on the web. But, it is still a very commonly asked topic. In order to improve your queries (applications) and databases performance, we create indexes.

But those created indexes may not be very useful over the period because of your application requirement changes, the queries against the data change, the structure of the database and tables changes, the data in the table change. Sooner or later you will find that Indexes that once helped performance now they are not so effective because of change in applications and databases.

Ultimately, SQL Server will start recommending you to create more indexes (missing indexes) to get the blazing performance of the queries.

There could be other scenarios like – your company is expanding the business/sites, they want to launch a couple of new applications, and those applications need more indexes on the table. Again you may end up with having more indexes.

Considering above the scenarios – if you don’t understand how to leverage the existing indexes by aligning them, you may end-up with over-indexing on the tables and an OLTP data tier.

How can over-indexing hurt your SQL server performance?

The reason that having too many indexes is a bad thing because it dramatically increases the amount of writing that needs to be done to the table.'...

http://www.sqlservercentral.com/blogs/sql-geek/2017/11/05/over-indexing-can-hurt-your-sql-server-performance/?utm_source=SSC&utm_medium=pubemail