Retrieves a description of the foreign key columns in the given foreign key
table that reference the primary key or the columns representing a unique constraint of the parent table (could be the same or a different table).
The number of columns returned from the parent table must match the number of
columns that make up the foreign key. They
are ordered by FKTABLE_CAT, FKTABLE_SCHEM, FKTABLE_NAME, and
KEY_SEQ.
Each foreign key column description has the following columns:
- PKTABLE_CAT String => parent key table catalog (may be
null
)
- PKTABLE_SCHEM String => parent key table schema (may be
null
)
- PKTABLE_NAME String => parent key table name
- PKCOLUMN_NAME String => parent key column name
- FKTABLE_CAT String => foreign key table catalog (may be
null
)
being exported (may be null
)
- FKTABLE_SCHEM String => foreign key table schema (may be
null
)
being exported (may be null
)
- FKTABLE_NAME String => foreign key table name
being exported
- FKCOLUMN_NAME String => foreign key column name
being exported
- KEY_SEQ short => sequence number within foreign key( a value
of 1 represents the first column of the foreign key, a value of 2 would
represent the second column within the foreign key).
- UPDATE_RULE short => What happens to
foreign key when parent key is updated:
- importedNoAction - do not allow update of parent
key if it has been imported
- importedKeyCascade - change imported key to agree
with parent key update
- importedKeySetNull - change imported key to
NULL
if
its parent key has been updated
- importedKeySetDefault - change imported key to default values
if its parent key has been updated
- importedKeyRestrict - same as importedKeyNoAction
(for ODBC 2.x compatibility)
- DELETE_RULE short => What happens to
the foreign key when parent key is deleted.
- importedKeyNoAction - do not allow delete of parent
key if it has been imported
- importedKeyCascade - delete rows that import a deleted key
- importedKeySetNull - change imported key to
NULL
if
its primary key has been deleted
- importedKeyRestrict - same as importedKeyNoAction
(for ODBC 2.x compatibility)
- importedKeySetDefault - change imported key to default if
its parent key has been deleted
- FK_NAME String => foreign key name (may be
null
)
- PK_NAME String => parent key name (may be
null
)
- DEFERRABILITY short => can the evaluation of foreign key
constraints be deferred until commit
- importedKeyInitiallyDeferred - see SQL92 for definition
- importedKeyInitiallyImmediate - see SQL92 for definition
- importedKeyNotDeferrable - see SQL92 for definition
Returns:
ResultSet
- each row is a foreign key column description
Parameters:
-
parentCatalog - a catalog name; must match the catalog name
as it is stored in the database; "" retrieves those without a
catalog;
null
means drop catalog name from the selection criteria
-
parentSchema - a schema name; must match the schema name as
it is stored in the database; "" retrieves those without a schema;
null
means drop schema name from the selection criteria
-
parentTable - the name of the table that exports the key; must match
the table name as it is stored in the database
-
foreignCatalog - a catalog name; must match the catalog name as
it is stored in the database; "" retrieves those without a
catalog;
null
means drop catalog name from the selection criteria
-
foreignSchema - a schema name; must match the schema name as it
is stored in the database; "" retrieves those without a schema;
null
means drop schema name from the selection criteria
-
foreignTable - the name of the table that imports the key; must match
the table name as it is stored in the database
Throws:
-
SQLException - if a database access error occurs
See Also:
DatabaseMetaData.getImportedKeys(java.lang.String, java.lang.String, java.lang.String)
,