Understanding Data Structures

A database is an organized collection of related objects. SQL is used throughout the database industry as a common method of issuing database queries. SQL is considered a language, composed of statements, functions, and data types. A SQL statement is used to access database objects using relational operations. Before we examine the SQL language, we need to understand some DB2 terminology. We will be referring to the basic data structures or objects that are defined for each DB2 database. These objects include

  • Tables

    - Data types

    - Aliases

    - Synonyms

  • Views

  • Indexes

    - Keys

  • Tablespaces

  • Index spaces

  • Databases

  • Storage Groups

Figure 2-1 shows the relationship between the DB2 objects.

Figure 2-1. A hierarchy of DB2 structures.

Tables ...

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