Create and install an Oracle database dictionary

Oracle Data Dictionary is mainly composed of tables and views. Its main function is to store the objects of some databases related to Oracle database structure information. The Oracle Database dictionary mainly describes the actual data organization. Processing them is the same as processing other database tables or views, but cannot be modified.

The Oracle Database dictionary is usually created when a database is created and installed. The Oracle Data dictionary is the basis for the work of the Oracle database system and is not supported by the data dictionary, the Oracle database system cannot do any work.

In the Oracle database dictionary, many views have three different instances whose prefixes are "USER _", "ALL _", and "DBA _". The database dictionary view prefixed with "USER _" usually records the information of the objects owned by the account that executes the query, the database dictionary view prefixed with "ALL _" usually records information about the objects owned by the account that executes the query and the objects owned by the account users authorized to PUBLIC, the Oracle Database dictionary view prefixed with "DBA _" contains information about all database objects regardless of the owner.

In other dictionary views, the main view is V $. This is because they all start with V $ or GV $. The V $ view is based on the X $ virtual view. The V $ view is owned by SYS users. By default, only SYS users and users with DBA system permissions can view all views, users without DBA permission can see the USER _ and ALL _ views, but not the DBA _ views. In contrast to database-oriented information in DBA _, ALL, and USER _ views, these views provide instance-oriented information visually.

In most data dictionary views of Oracle, there are view families like DBA_TABLES, ALL_TABLES, and USER_TABLES. There are more than 100 view families in Oracle. The following table lists the most important and commonly used view families. Note that each view family has a DBA _, one ALL _ and one USER _ view.

View family description

COL_PRIVS includes the column permissions of the table, including the grants, grants, and permissions.

EXTENTS data range information, such as data file, data segment name (segment_name) and size

INDEXES index information, such as type, uniqueness, and involved table

IND_COLUMNS index column information, such as the column sorting method on the index

OBJECTS object information, such as status and DDL time

ROLE_PRIVS role permissions, such as GRANT and ADMIN options

Segment information of the SEGMENTS table and index, such as tablespace and storage

SEQUECNCES sequence information, such as sequence cache, cycle, and ast_number

SOURCE code of all built-in processes, functions, and packages except triggers

SYNONYMS alias information, such as the referenced object and the Oracle database link db_link

SYS_PRIVS system permissions, such as grantee, privilege, and admin options

TAB_COLUMNS table and View column information, including the column data type

TAB_PRIVS table permissions, such as grant, granted, and permissions

TABLES Table information, such as the number of tablespaces, storage parameters, and data rows

TRIGGERS trigger information, such as type, event, trigger body)

USERS user information, such as temporary and default tablespace

VIEWS, including view Definitions

There are also some uncommon data dictionary tables in Oracle, but these tables are not really dictionary families, they are all important single views. The following table lists these views:

View Name Description

The USER_COL_PRIVS_MADE User grants column permissions to others.

Column permissions obtained by the USER_COL_PRIVS_RECD user

USER_TAB_PRIVS_MADE the table permission granted to others

Table permissions granted by the USER_TAB_PRIVS_RECD user

The above content is an introduction to the Oracle database dictionary. I hope you will have some gains.