Second result set has them concatenated with a. use AdventureWorks2012įirst result set, schema and table name are different columns. You will not see anything until the query is completed. Note, this query takes a few seconds (or minutes depending on speed of machine and database size) to run. I give an example below to show you how it works. The only new elements you will notice here is that I am combining TABLE_SCHEMA+’.’+TABLE_NAME. If you do not know cursors in SQL, check out my previous lesson on cursors: SQL: Learn to use Cursors – List table names If you want to Reindex all the tables in a database, you can do it using a Cursor and While loop. It gives a little wiggle room for the real life functionality of the database. That is why you will often see 80 or 90 used as a fill factor. If the data was stagnant that could work, but when data is constantly being written and deleted, the indexes need room for correction. A fill factor of 0 or 100 tells SQL to fill every index page completely – leave no extra room. The syntax below is as follows: DBCC DBREINDEX(TABLE NAME, Index you want to rebuild (‘ ‘ = all indexes), fillfactor) DBCC DBREINDEX(.,' ',90)Ī quick note on fill factor. It is a list of useful tools you can use to administer a SQL Server. Or you can use the follow SQL Code Reindex CodeĭBCC stands for Database Console Commands. If you want to rebuild all the indexes in a table, you can click on the Index folder and click Rebuild All This time click RebuildĬlick Okay and the window and your Index will be rebuilt. Note my index is 66.67% fragmented.Ĭlick out of that window and right click on your index again. Select Fragmentation from the Select a page window. Right click on an index and go to Properties
You can think of it as the master index for that table if it helps. I won’t go in depth on Clustered vs Non-Clustered, only know the each table can only have 1 Clustered Index. You can find Indexes nested under tables in the Object Explorer. You can do it which just a few mouse clicks.įirst, let’s find our indexes. The act of defragging an index in SQL Server is known as rebuilding. Make sure the database is not being used before trying anything in this lesson. ***Don’t attempt this on a production database while it is in use. After a while this fragmentation can start to have an effect on your database’s performance. The problem is, with all the constant reading and writing to a live database, the indexes quickly become fragmented as they try to keep up will all the new data coming and going. Databases use indexes so they do not have to look at every single row in a table that could contain hundreds of thousands up to billions of rows. Instead of having to look at each page in a book for something, you can just go to the index – find your topic in an alphabetized list, and go to the page number indicated.
Indexes in databases work kind of like an index in a book.
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