FOREIGN_KEYS Rowset

The FOREIGN_KEYS rowset identifies the foreign key columns defined in the catalog by a given user. This schema rowset is built upon several SQL92 schema views as a convenience to the non-SQL programmer, and, if supported, this must be synchronized with the related SQL92 views (REFERENTIAL_CONSTRAINTS and CONSTRAINT_COLUMN_USAGE).

The FOREIGN_KEYS rowset contains the following columns

Column name Type indicator Description
PK_NAME DBTYPE_WSTR Primary key name. NULL if the provider does not support named primary key constraints. This column is not returned by 1.x providers.
PK_TABLE_CATALOG DBTYPE_WSTR Catalog name in which the primary key table is defined. NULL if the provider does not support catalogs.
PK_TABLE_SCHEMA DBTYPE_WSTR Unqualified schema name in which the primary key table is defined. NULL if the provider does not support schemas.
PK_TABLE_NAME DBTYPE_WSTR Primary key table name.
PK_COLUMN_NAME DBTYPE_WSTR Primary key column name. This column, together with the PK_COLUMN_GUID and PK_COLUMN_PROPID columns, forms the column ID. One or more of these columns will be NULL depending on which elements of the DBID structure the provider uses.
PK_COLUMN_GUID DBTYPE_GUID Primary key column GUID.
PK_COLUMN_PROPID DBTYPE_UI4 Primary key column property ID.
FK_NAME DBTYPE_WSTR Foreign key name. NULL if the provider does not support named foreign key constraints. This column is not returned by 1.x providers.
FK_TABLE_CATALOG DBTYPE_WSTR Catalog name in which the foreign key table is defined. NULL if the provider does not support catalogs.
FK_TABLE_SCHEMA DBTYPE_WSTR Unqualified schema name in which the foreign key table is defined. NULL if the provider does not support schemas.
FK_TABLE_NAME DBTYPE_WSTR Foreign key table name.
FK_COLUMN_NAME DBTYPE_WSTR Foreign key column name. This column, together with the FK_COLUMN_GUID and FK_COLUMN_PROPID columns, forms the column ID. One or more of these columns will be NULL depending on which elements of the DBID structure the provider uses.
FK_COLUMN_GUID DBTYPE_GUID Foreign key column GUID.
FK_COLUMN_PROPID DBTYPE_UI4 Foreign key column property ID.
ORDINAL DBTYPE_UI4 The order of the column names (and GUIDs and property IDs) in the key. For example, a table might contain several foreign key references to another table. The ordinal starts over for each reference; for example, two references to a three-column key would return 1, 2, 3, 1, 2, 3.
UPDATE_RULE DBTYPE_WSTR If an <update rule> was specified, then the UPDATE_RULE value is one of the following:

"CASCADE"—A <referential action> of CASCADE was specified.

"SET NULL"—A <referential action> of SET NULL was specified.

"SET DEFAULT"—A <referential action> of SET DEFAULT was specified.

"NO ACTION"—A <referential action> of NO ACTION was specified.

Providers should return NULL only if they cannot determine the UPDATE_RULE. In most cases, this implies a default of NO ACTION.

DEFERRABILITY DBTYPE_12 Deferrability of the foreign key.  Value is one of the following:

DBPROPVAL_DF_INITIALLY_DEFERRED

DBPROPVAL_DF_INITIALLY_IMMEDIATE

DBPROPVAL_DF_NOT_DEFERRABLE

This column is not returned by 1.x providers.

DELETE_RULE DBTYPE_WSTR If a <delete rule> was specified then the DELETE_RULE value is one of the following:

"CASCADE"—A <referential action> of CASCADE was specified.

"SET NULL"—A <referential action> of SET NULL was specified.

"SET DEFAULT"—A <referential action> of SET DEFAULT was specified.

"NO ACTION"—A <referential action> of NO ACTION was specified.

Providers should return NULL only if they cannot determine the DELETE_RULE. In most cases, this implies a default of NO ACTION.


Default Sort Order: FK_TABLE_CATALOG, FK_TABLE_SCHEMA, FK_TABLE_NAME