DB2 Features

Shops run their business data on DB2 because of a set of features that plain files cannot give: shared access, enforced rules, ad-hoc queries, and built-in recovery. This page lists the features that matter most.

Advantages of a DBMS

• Provides facilities to developers to define data to the system.
• Provides facilities to users or programs to retrieve or change the data.
• Provides facilities for security and recovery, so data is protected and restorable.
• Maintains information consistency throughout the database, so every user sees the same correct data.

Relational model features

• Data is stored as tables with rows and columns, which is simple to understand.
• Tables are related through primary keys and foreign keys instead of physical pointers.
• SQL is one language for both defining objects and manipulating data.
• Normalization is a design method that reduces data redundancy and protects against update and delete anomalies.
• New entities, attributes and relations can be added, and old ones deleted, without rebuilding everything.

DB2 storage and performance features

• Tablespaces organize physical storage: simple (the default), segmented (ideal for more than one table, especially small tables), and partitioned (one table split by boundary values of specific columns).
• Indexes give fast access to rows by column value.
• Views present any or all of the data in one or more tables without storing a copy.
• Bufferpools keep recently read data in memory, so the next request does not re-read the disk.
• Synonyms and aliases let programs use short or location-independent names for tables and views.