Managing Databases in SQL Server Analysis Services

This document provides a comprehensive guide to managing databases within SQL Server Analysis Services (SSAS). Effective database management is crucial for the performance, security, and usability of your multidimensional and tabular models.

Overview of SSAS Databases

An Analysis Services database is a container for multidimensional or tabular data models, along with their associated metadata, security roles, and processing information. Key aspects include:

  • Data Models: The core structures (cubes, dimensions, tables, measures) that hold your analytical data.
  • Metadata: Definitions of objects, properties, and relationships within the database.
  • Security: Definitions of roles and permissions to control access to data.
  • Processing Information: Logs and status related to data synchronization and refresh operations.

Common Database Management Tasks

Creating a New Database

You can create a new Analysis Services database using SQL Server Management Studio (SSMS) or programmatically using AMO (Analysis Management Objects) or TOM (Tabular Object Model).

Using SSMS:

  1. Connect to your SSAS instance in SSMS.
  2. Right-click on the "Databases" folder.
  3. Select "New Database...".
  4. Enter a name for your database and configure basic properties.

Using AMO/TOM:

This involves writing C# or other .NET code to interact with the SSAS server object model.


// Example using AMO (Conceptual)
Server server = new Server();
server.Connect("YourServerName");
Database newDb = new Database("MyNewDatabase");
server.Databases.Add(newDb);
newDb.Update();
Backing Up and Restoring Databases

Regular backups are essential for disaster recovery. Analysis Services supports full backups, differential backups, and transaction log backups (for Tabular in Compatibility Level 1200+).

Backup Methods:

  • SSMS: Navigate to the database, right-click, select "Tasks" -> "Backup...".
  • SQL Server Agent Jobs: Automate backups using jobs that execute Analysis Services XMLA commands or AMO scripts.
  • PowerShell/AMO: Script backup operations for advanced automation.

Restore Methods:

  • SSMS: Navigate to the "Databases" folder, right-click, select "Restore" -> "Database...".
  • SSMS (Overwrite): To restore over an existing database, use the "Options" page in the restore dialog and select "Overwrite the existing database (WITH REPLACE)".

A typical backup command using XMLA:


<Backup xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">
    <Object>
        <DatabaseID>YourDatabaseName</DatabaseID>
    </Object>
    <File>C:\Backup\YourDatabaseName_Full.abf</File>
    <BackupSecurity>true</BackupSecurity>
    <StorageLocation>
        <FileID>C:\Backup\YourDatabaseName_Full.abf</FileID>
    </StorageLocation>
</Backup>
Processing Databases and Objects

Processing is the operation that loads data into the Analysis Services database structures. You can process the entire database, specific models, or individual objects (tables, partitions, dimensions).

Processing Levels:

  • Full Process: Clears and reprocesses all data.
  • Process Update: Updates existing data and adds new data.
  • Process Add: Adds new data without affecting existing data.
  • Process Default: Performs the most efficient processing for each object.

Processing Methods:

  • SSMS: Right-click on the database or object and select "Process...".
  • SQL Server Agent Jobs: Use Analysis Services Processing Tasks.
  • XMLA Scripts: Execute process commands directly.
  • AMO/TOM: Programmatically initiate processing.

Example XMLA for processing a database full:


<Process xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">
    <Object>
        <DatabaseID>YourDatabaseName</DatabaseID>
    </Object>
    <Type>ProcessFull</Type>
    <Data>
        <ErrorConfiguration>
            <KeyErrorAction>Continue</KeyErrorAction>
            <KeyErrorLimitAction>Stop</KeyErrorLimitAction>
            <KeyErrorLimit>0</KeyErrorLimit>
            <KeyErrorLogFile>C:\SSAS_Errors.log</KeyErrorLogFile>
        </ErrorConfiguration>
    </Data>
</Process>
Detaching and Attaching Databases

Similar to relational databases, SSAS databases can be detached and attached. This is useful for moving databases between servers or archiving them.

Detaching:

  • In SSMS, right-click the database and select "Tasks" -> "Detach...".
  • Confirm the detach operation. The database files will be removed from the server's data directory.

Attaching:

  • In SSMS, right-click the "Databases" folder and select "Attach...".
  • Browse to the location of the detached database files (.xmla or .asdatabase and associated data files).
  • Select the primary database file and click "OK".

Note: Detaching and attaching requires stopping the SSAS service if the files are in use.

Deleting Databases

You can delete an Analysis Services database if it is no longer needed.

Using SSMS:

  1. Connect to your SSAS instance.
  2. Right-click on the database you wish to delete.
  3. Select "Delete".
  4. Confirm the deletion. This operation is irreversible and will permanently remove the database and all its data and metadata.

Security Considerations

Managing permissions is critical. Analysis Services databases use roles defined at the database level. Users can be granted specific permissions (e.g., Read, ReadDefinition, Process, Administrator) on the database or its objects.

Refer to the Security Management section for detailed guidance.