S y s te m
In s t a n c e
D a ta b a s e
D a t a b a s e p a r t it io n g r o u p
T a b le s p a c e s Ta b le s In d e x e s L o n g d a ta
Figure 2-1 Database objects relationship
Instances (database managers) An instance (also known as a database manager) is DB2 code that manages data. It controls what can be done to the data, and manages system resources that are assigned to it. Each instance is a complete environment. If the database system is parallel, it contains all of the database partitions. An instance has its own databases (which other instances cannot access), and all its database partitions share the same system directories. It also has separate security from other instances on the same machine or system.
Databases A relational database presents data as a collection of tables. A table consists of a defined number of columns and any number of rows. Each database includes a set of system catalog tables that describe the logical and physical structure of the data, a configuration file containing the parameter values allocated for the database, and a recovery log with ongoing transactions and transactions to be archived.
Chapter 2. Content Manager base products
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