Defragmenting Table Indexes in SQL Server

Q

How To Defragment Table Indexes in SQL Server?

✍: FYIcenter.com

A

When a table index is fragmented to a certain percentage, you need to defragment the index to maintain its performance level. There are 3 ways to defragment:

1. "ALTER INDEX index_name ON table_name REORGANIZE" - Defragmenting the specified index performed in online mode. No locks applied on affected table. Used for indexes with a small fragmentation percentage.

2. "ALTER INDEX index_name ON table_name REBUILD" - Defragmenting the specified index performed in offline mode by default. It can be performed in online mode. Used for indexes with a large fragmentation percentage.

3. "CREATE INDEX ... WITH (DROP_EXISTING = ON)" - Re-creating the specified index. The definition of the index can be changed.

⇒ "ALTER INDEX ... REORGANIZE" - Defragmenting Indexes in SQL Server

⇐ What Causes Index Fragmentation in SQL Server

⇑ Understanding and Managing Indexes in SQL Server

⇑⇑ SQL Server Database Tutorials

2016-11-08, 2106🔥, 0💬

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What Is Index Fragmentation in SQL Server
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Understanding and Managing Views in SQL Server
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Index Speeding Up SELECT Statements in SQL Server
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How To Rebuild All Indexes on a Single Table in SQL Server? If you have several indexes on a single table and want to rebuild all of them, you may use the "ALTER INDEX ALL ON table_name REBUILD" statement as shown in the tutorial exercise below: USE FyiCenterData; GO UPDATE fyi_links_indexed SET url... 2016-11-08, 2179🔥, 0💬

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What Happens If You Add a New Index to Large Table in SQL Server? An index can be added when you create a new table. New rows will be indexed as they are inserted into the table. But you can also add a new index to an existing table with the same CREATE INDEX statement. The existing rows will be ind... 2016-11-13, 2167🔥, 0💬

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