Overview: Accelerating queries with Informix Warehouse Accelerator

You can set up query acceleration with Informix® Warehouse Accelerator by following a few installation and configuration steps. Before you begin, plan the installation by reviewing the architecture and administration options.

1. Install, start, and prepare the Informix database server for Informix Warehouse Accelerator.

   Ensure that user informix has write access to the sqlhosts file and set up a default sbspace.

2. Design and implement a dimensional database that uses a star or snowflake schema.

   Ensure that the database uses the data types, functions, expressions, and joins that are supported by Informix Warehouse Accelerator.

3. Install Informix Warehouse Accelerator.

   Determine the best installation architecture for your business needs and your hardware. You can install Informix Warehouse Accelerator on the same computer as the Informix database server, on a different computer, or on a hardware cluster. Review the installation prerequisites and requirements and determine which tool you want to use to administer Informix Warehouse Accelerator.

4. Grant the appropriate permissions to users for administering Informix Warehouse Accelerator. Users must be user informix, have the DBA role, or have the WAREHOUSE privilege.

   You can use IBM® OpenAdmin Tool (OAT) for Informix, Informix Smart Analytics Optimizer Studio, or run SQL routines or Java™ classes from the command line.

5. Configure and start the accelerator server.

   Identify the network interface, create a storage directory, and edit the dwainst.conf configuration file. You then run the ondwa setup command to create the files and subdirectories that are required to run the accelerator server. You run the ondwa start command to start the accelerator server.

6. Create an accelerator by configuring a connection between the accelerator server to the database server.

   You specify an accelerator name and connection information.

7. Create and load a data mart.

   You can use any of the administration tools to create and load a data mart. You can design a data mart yourself or use workload analysis to design an effective data mart that is based on your data and queries. You can use workload analysis by running Informix Warehouse Accelerator routines or by using OAT.

8. Turn on query acceleration by setting the use_dwa environment variable to accelerate on.

   You run an SQL statement from the database client to set the use_dwa environment variable.

After you turn on query acceleration, the client application sends queries to the database server. The SQL optimizer on the database server matches the queries that can be accelerated to the AQTs and sends the queries to the accelerator server. The results are returned to the database server, which sends the results to the client application.