exportedkeys

Retrieve information about exported foreign keys

Syntax

e = exportedkeys(dbmeta, 'cata', 'sch')
e = exportedkeys(dbmeta, 'cata', 'sch', 'tab')

Description

e = exportedkeys(dbmeta, 'cata', 'sch') returns foreign exported key information (that is, information about primary keys that are referenced by other tables) for the schema sch, of the catalog cata, for the database whose database metadata object is dbmeta.

e = exportedkeys(dbmeta, 'cata', 'sch', 'tab') returns exported foreign key information for the table tab, in the schema sch, of the catalog cata, for the database whose database metadata object is dbmeta.

Examples

Get foreign exported key information for the schema SCOTT for the database metadata object dbmeta.

e = exportedkeys(dbmeta,'orcl','SCOTT')
e = 
  Columns 1 through 7
    'orcl'   'SCOTT'   'DEPT'   'DEPTNO'    'orcl'...
    'SCOTT'    'EMP'
  Columns 8 through 13
    'DEPTNO'    '1'    'null'    '1'    'FK_DEPTNO'...    
		'PK_DEPT'

The results show the foreign exported key information.

ColumnDescriptionValue

1

Catalog containing primary key that is exported

null

2

Schema containing primary key that is exported

SCOTT

3

Table containing primary key that is exported

DEPT

4

Column name of primary key that is exported

DEPTNO

5

Catalog that has foreign key

null

6

Schema that has foreign key

SCOTT

7

Table that has foreign key

EMP

8

Foreign key column name, that is the column name that references the primary key in another table

DEPTNO

9

Sequence number within the foreign key

1

10

Update rule, that is, what happens to the foreign key when the primary key updates

null

11

Delete rule, that is, what happens to the foreign key when the primary key is deleted

1

12

Foreign key name

FK_DEPTNO

13

Primary key name that is referenced by foreign key

PK_DEPT

In the schema SCOTT, only one primary key is exported to (referenced by) another table. DEPTNO, the primary key of the table DEPT, is referenced by the field DEPTNO in the table EMP. The referenced table is DEPT and the referencing table is EMP. In the DEPT table, DEPTNO is an exported key. Reciprocally, the DEPTNO field in the table EMP is an imported key.

For a description of codes for update and delete rules, see the getExportedKeys property on the Oracle® Java® Web site:

http://docs.oracle.com/javase/7/docs/api/java/sql/DatabaseMetaData.html.

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