Category: Series

• 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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• 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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• The Index Allocation Map (IAM)

  

  2014-04-02 - General, Series, SQL Server Internals, Storage Wednesday

  SQL Server tracks the pages that belong to an allocation unit through special index allocation map pages, also called IAM pages. Each IAM page covers a single GAM-interval of the database file. All IAM pages of a single allocation unit together build an IAM-chain. Read on to find out more.

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• Salt – Preventing Rainbow Attacks against Password Stores

  

  2014-03-31 - Cryptographic Terminology, Cryptography, General, Security, Series

  What is a Salt Value and how does it help to protect the stored passwords of your application’s users from attacks involving Rainbow Tables? Read on to find out now.

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• Cryptographic Hash Functions

  

  2014-03-30 - Cryptographic Terminology, Cryptography, General, Security, Series

  Hash functions calculate a fixed length binary digest of a document. Read on to see what additional requirements turn an ordinary hash function into a cryptographic hash function and what use cases require the use of cryptographic hash functions.

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