Tag: storage engine

• Intermediate Index Pages in SQL Server

  

  2014-07-02 - General, Series, SQL Server Internals, Storage Wednesday

  SQL Server stores indexes in B+ Tree format on disk. Each node is represented by a SQL Server page. The actual rows are stored in data pages while the index structure resides in intermediate index pages. Read on to find out more.

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• Where are my Rows? – Using the %%physloc%% Virtual Column

  

  2014-06-25 - DMVs & CVs, General, Series, SQL Server Internals, Storage Wednesday

  Sometimes it is helpful to know on which page exactly SQL Server has stored a particular row. You can use the undocumented %%physloc%% virtual column, together with its supporting functions sys.fn_PhysLocFormatter and sys.fn_PhysLocCracker, to find out.

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• B+Trees – How SQL Server Indexes are Stored on Disk

  

  2014-06-18 - General, Series, SQL Server Internals, Storage Wednesday

  How does SQL Server organize clustered and non-clustered indexes on disk? SQL server uses B+Trees. Read on to find out what B+Trees are and how they are implemented in SQL Server.

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• Bulk Changed Map (BCM): The Minimally Logged Advantage

  

  2014-05-14 - General, Series, SQL Server Internals, Storage Wednesday

  The Bulk-Logged recovery mode can provide a performance gain for your database. Check out how SQL Server uses the Bulk Changed Map to make this possible.

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• Differential Changed Map (DCM): How SQL Server Tracks Changed Pages

  

  2014-05-07 - Backup, General, Series, SQL Server Internals, Storage Wednesday

  SQL Server uses the Differential Changed Map to determine, which pages changed since the last full backup. Read on to find out how the DCM is working.

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