IBM DB2 manual Collecting information about the database, Database creation, Database layout, 217

5.2.1 Collecting information about the database

To deploy a pre-configured database to a new system, the tasks include these:

￿Create the database.

￿Create the database layout.

￿Create the database objects.

Database creation

The database can be created by executing the CREATE DATABASE command through the Command Line Processor (CLP) or by using one of the DB2 APIs.

Note: In this chapter we use Java as a programming language. DB2 does not provide APIs for Java. DB2 provides APIs for C/C++ and COBOL.

In Example 5-1we show how to use the CREATE DATABASE command to create our ITSODB database.

Example 5-1 Statement to create the ITSODB sample database

CREATE DATABASE ITSODB ON /db2 ALIAS ITSO

Database layout

Database layout is about buffer pools and table spaces. A table space is a logical storage unit or an abstraction of the physical storage. The mapping from table space to storage devices is handled by the containers. A table space consists of one or more containers that map directly to raw devices or files on a storage device.

We use table spaces to group tables and indexes logically. When deploying the pre-configured database, these logical groups can be mapped differently on the target system based on the storage availability and data column.

A buffer pool is an in-memory cache for data. A table space is associated with a buffer pool in the table space definition. One buffer pool can be the cache for data in several table spaces. Figure 5-2illustrates two different ways to map buffer pool, table spaces, and storage for the sample database ITSODB.

Chapter 5. Deploying pre-configured databases 217