RDB$FILTERS

Reserved Words and KeywordsMonitoring Tables

`RDB$FILTERS`

RDB$FILTERS stores information about BLOB filters.

Column Name Data Type Description

Column Name	Data Type	Description
`RDB$FUNCTION_NAME`	`CHAR(63)`	The unique identifier of the `BLOB` filter
`RDB$DESCRIPTION`	`BLOB TEXT`	Documentation about the `BLOB` filter and the two subtypes it is used with, written by the user
`RDB$MODULE_NAME`	`VARCHAR(255)`	The name of the dynamic library or shared object where the code of the `BLOB` filter is located
`RDB$ENTRYPOINT`	`CHAR(255)`	The exported name of the `BLOB` filter in the filter library.Note, this is often not the same as `RDB$FUNCTION_NAME`, which is the identifier with which the `BLOB` filter is declared to the database
`RDB$INPUT_SUB_TYPE`	`SMALLINT`	The `BLOB` subtype of the data to be converted by the function
`RDB$OUTPUT_SUB_TYPE`	`SMALLINT`	The `BLOB` subtype of the converted data
`RDB$SYSTEM_FLAG`	`SMALLINT`	Flag indicating whether the filter is user-defined or internally defined: `0` - user-defined `1` or greater - internally defined
`RDB$SECURITY_CLASS`	`CHAR(63)`	May reference a security class defined in the table `RDB$SECURITY_CLASSES`, to apply access control limits to all users of this filter
`RDB$OWNER_NAME`	`CHAR(63)`	The username of the user who created the filter originally

RDB$FUNCTION_NAME

CHAR(63)

The unique identifier of the BLOB filter

RDB$DESCRIPTION

BLOB TEXT

Documentation about the BLOB filter and the two subtypes it is used with, written by the user

RDB$MODULE_NAME

VARCHAR(255)

The name of the dynamic library or shared object where the code of the BLOB filter is located

RDB$ENTRYPOINT

CHAR(255)

The exported name of the BLOB filter in the filter library.Note, this is often not the same as RDB$FUNCTION_NAME, which is the identifier with which the BLOB filter is declared to the database

RDB$INPUT_SUB_TYPE

SMALLINT

The BLOB subtype of the data to be converted by the function

RDB$OUTPUT_SUB_TYPE

SMALLINT

The BLOB subtype of the converted data

RDB$SYSTEM_FLAG

SMALLINT

Flag indicating whether the filter is user-defined or internally defined:

0 - user-defined
1 or greater - internally defined

RDB$SECURITY_CLASS

CHAR(63)

May reference a security class defined in the table RDB$SECURITY_CLASSES, to apply access control limits to all users of this filter

RDB$OWNER_NAME

CHAR(63)

The username of the user who created the filter originally

`RDB$FORMATS`

RDB$FORMATS stores information about changes in tables.Each time any metadata change to a table is committed, it gets a new format number.When the format number of any table reaches 255, or any view 32,000, the entire database becomes inoperable.To return to normal, the database must be backed up with the gbak utility and restored from that backup copy.

Column Name Data Type Description

Column Name	Data Type	Description
`RDB$RELATION_ID`	`SMALLINT`	Table or view identifier
`RDB$FORMAT`	`SMALLINT`	Table format identifier — maximum 255 for tables, 32,000 for views.The critical time comes when this number approaches 255 for any table or 32,000 for any view
`RDB$DESCRIPTOR`	`BLOB FORMAT`	Stores column names and data attributes as `BLOB`, as they were at the time the format record was created

RDB$RELATION_ID

SMALLINT

Table or view identifier

RDB$FORMAT

SMALLINT

Table format identifier — maximum 255 for tables, 32,000 for views.The critical time comes when this number approaches 255 for any table or 32,000 for any view

RDB$DESCRIPTOR

BLOB FORMAT

Stores column names and data attributes as BLOB, as they were at the time the format record was created