Appendix D. System Tables

When you create a database, the Firebird engine creates a lot of system tables. Metadata — the descriptions and attributes of all database objects — are stored in these system tables.

System table identifiers all begin with the prefix RDB$.

List of System Tables
RDB$BACKUP_HISTORY

History of backups performed using nBackup

RDB$CHARACTER_SETS

Names and describes the character sets available in the database

RDB$CHECK_CONSTRAINTS

Cross-references between the names of constraints (NOT NULL constraints, CHECK constraints and ON UPDATE and ON DELETE clauses in foreign key constraints) and their associated system-generated triggers

RDB$COLLATIONS

Collation sequences for all character sets

RDB$DATABASE

Basic information about the database

RDB$DEPENDENCIES

Information about dependencies between database objects

RDB$EXCEPTIONS

Custom database exceptions

RDB$FIELDS

Column and domain definitions, both system and custom

RDB$FIELD_DIMENSIONS

Dimensions of array columns

RDB$FILES

Information about secondary files and shadow files

RDB$FILTERS

Information about BLOB filters

RDB$FORMATS

Information about changes in the formats of tables

RDB$FUNCTIONS

Information about external functions

RDB$FUNCTION_ARGUMENTS

Attributes of the parameters of external functions

RDB$GENERATORS

Information about generators (sequences)

RDB$INDEX_SEGMENTS

Segments and index positions

RDB$INDICES

Definitions of all indexes in the database (system- or user-defined)

RDB$LOG_FILES

Not used in the current version

RDB$PAGES

Information about database pages

RDB$PROCEDURE_PARAMETERS

Parameters of stored procedures

RDB$PROCEDURES

Definitions of stored procedures

RDB$REF_CONSTRAINTS

Definitions of referential constraints (foreign keys)

RDB$RELATION_CONSTRAINTS

Definitions of all table-level constraints

RDB$RELATION_FIELDS

Top-level definitions of table columns

RDB$RELATIONS

Headers of tables and views

RDB$ROLES

Role definitions

RDB$SECURITY_CLASSES

Access control lists

RDB$TRANSACTIONS

State of multi-database transactions

RDB$TRIGGER_MESSAGES

Trigger messages

RDB$TRIGGERS

Trigger definitions

RDB$TYPES

Definitions of enumerated data types

RDB$USER_PRIVILEGES

SQL privileges granted to system users

RDB$VIEW_RELATIONS

Tables that are referred to in view definitions: one record for each table in a view

D.1. RDB$BACKUP_HISTORY

RDB$BACKUP_HISTORY stores the history of backups performed using the nBackup utility.

Column NameData TypeDescription

RDB$BACKUP_ID

INTEGER

The identifier assigned by the engine

RDB$TIMESTAMP

TIMESTAMP

Backup date and time

RDB$BACKUP_LEVEL

INTEGER

Backup level

RDB$GUID

CHAR(38)

Unique identifier

RDB$SCN

INTEGER

System (scan) number

RDB$FILE_NAME

VARCHAR(255)

Full path and file name of backup file