Exploring the Contents of the Data Dictionary

This section examines the data dictionaries of three RDBMS vendors, Oracle, Sybase, and to a smaller degree, MySQL. Although the implementations have unique specifications for their data dictionaries, they serve the same function. Don't concern yourself with the different names of the system tables; simply focus on the concept of a data dictionary and the data it contains.

Oracle's Data Dictionary

Because every table must have an owner, the owner of the system tables in an Oracle data dictionary is SYS. Oracle's data dictionary tables are divided into three basic categories: user accessible views, DBA views, and dynamic performance tables, which also appear as views. Views that are accessible to a ...

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