Category: General

• The Global Allocation Map (GAM)

  

  2014-04-16 - General, Series, SQL Server Internals, Storage Wednesday

  SQL Server uses the Global Allocation Map (GAM) to catalog if an extent is allocated or not. In a 7988-byte bitmap each extent is associated with a single bit to convey that information. Read on to get all the details.

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• Scripting All Logins on a SQL Server Instance

  

  2014-04-14 - General, Queries, Security

  Scripting all logins on a SQL Server instance can be helpful e.g. when setting up a test or development environment. Read on to see an example query for just this purpose.

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• How to Re-Create a Login with only a Hashed Password

  

  2014-04-13 - General, Security

  To re-create a login on a different SQL Server instance while preserving the password you can use the CREATE LOGIN statement with the hashed password. Read on for a detailed explanation.

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• How to Fix Orphaned Users in SQL Server

  

  2014-04-11 - General, Security

  To access a database in SQL Server, a login needs to have an associated user in that database. Read on to see how that association is implemented and what you need to do to repair it if it breaks.

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• The GAM Interval and GAM Extents

  

  2014-04-09 - General, Series, SQL Server Internals, Storage Wednesday

  What is a GAM extent in SQL Server? What is a GAM Interval and how big is it really? Read on now to get the answers to these questions and see why a GAM interval is not 64000 extents.

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