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SQL Index Fragmentation - Important or Not?

I'm looking at database monitoring and seeing that nearly all of our SQL databases report a high degree of fragmentation in their indexes. 99.8-99.9% fragmented is not uncommon. Can this play significantly into poorer performance for database interactions from .NET web servers which integrate with SQL?
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Database Administrator / Software Engineer
Commented:
Hi,

Yes, fragmented indexes can slow things down.
I highly recommend that you reorg both your indexes and tables that are fragmented.

https://docs.microsoft.com/en-us/sql/relational-databases/indexes/reorganize-and-rebuild-indexes?view=sql-server-ver15

Regards,
    Tomas Helgi
lcohanDatabase Analyst
Commented:
Physical fragmentation is in particular very bad however overall fragmentation depends on many factors (including FILLFACTOR) and of you don't have your own maintenance SQL code already you can have a look at Ola's advice/scripts that can be found here https://ola.hallengren.com/sql-server-index-and-statistics-maintenance.html and I believe are pretty much trusted and used across Microsoft SQL server community.