Release 8.1.7
Part Number A88714-01
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| Oracle Heterogeneous Services Release 8.1.7 Part Number A88714-01 |
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Generic connectivity agents translate a query that refers to an Oracle8i data dictionary table into a query that retrieves the data from a non-Oracle data dictionary. You perform queries on data dictionary tables over the database link in the same way you query data dictionary tables in Oracle8i. The generic connectivity data dictionary is similar to the Oracle8i data dictionary in appearance and use. Non-Oracle data dictionary information is supplied to the user in Oracle8i data dictionary format.
To better understand the data dictionary support provided by generic connectivity, read these sections:
Data dictionary information is stored in the non-Oracle system as system tables and accessed through ODBC or OLE DB application programming interfaces (APIs). This section contains the following topics:
Accessing a non-Oracle data dictionary table or view is identical to accessing a data dictionary in an Oracle database. You issue a SELECT statement specifying a database link. The Oracle8i data dictionary view and column names are used to access the non-Oracle data dictionary. Synonyms of supported views are also acceptable.
For example, the following statement queries the data dictionary table ALL_USERS to retrieve all users in the non-Oracle system:
SQL> SELECT * FROM all_users@sid1;
When you issue a data dictionary access query, the ODBC or OLE DB agent:
Generic connectivity supports only these views and tables:
If you use an unsupported view, then you receive the Oracle8i message for no rows selected.
If you want to query data dictionary views using SELECT ... FROM DBA_*, first connect as Oracle user SYSTEM or SYS. Otherwise, you receive the following error message:
ORA-28506: Parse error in data dictionary translation for %s stored in %s
Using generic connectivity, queries of the supported data dictionary tables and views beginning with the characters "ALL_" may return rows from the non-Oracle system when you do not have access privileges for those non-Oracle objects. When querying an Oracle database with the Oracle data dictionary, rows are returned only for those objects you are permitted to access.
The tables in this section list Oracle data dictionary view names and the equivalent ODBC or OLE DB APIs used.
The generic connectivity data dictionary differs from a typical Oracle database server data dictionary. The Oracle database server columns that are missing in a non-Oracle data dictionary table are filled with the following, depending on the column type:
The generic connectivity data dictionary tables and views provide this information:
In the descriptions that follow, the values in the Null? column may differ from the Oracle8i data dictionary tables and views. Any default value is shown to the right of an item.
| Name | Null? | Type | Value |
|---|---|---|---|
|
OWNER |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_TYPE |
|
VARCHAR2(11) |
"TABLE" or "VIEW" or "SYNONYM" |
| Name | Null? | Type | Value |
|---|---|---|---|
|
OWNER |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
COLUMN_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
COMMENTS |
|
VARCHAR2(4000) |
NULL |
| Name | Null? | Type | Value |
|---|---|---|---|
|
OWNER |
NOT NULL |
VARCHAR2(30) |
|
|
CONSTRAINT_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
COLUMN_NAME |
|
VARCHAR2(4000) |
|
|
POSITION |
|
NUMBER |
|
| Name | Null? | Type | Value |
|---|---|---|---|
|
OWNER |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_TYPE |
|
VARCHAR2(11) |
"TABLE" or "VIEW" |
|
COMMENTS |
|
VARCHAR2(4000) |
NULL |
| Name | Null? | Type | Value |
|---|---|---|---|
|
USERNAME |
NOT NULL |
VARCHAR2(30) |
|
|
USER_ID |
NOT NULL |
NUMBER |
0 |
|
CREATED |
NOT NULL |
DATE |
NULL |
| Name | Null? | Type | Value |
|---|---|---|---|
|
TABLE_NAME |
|
VARCHAR2(30) |
|
|
COMMENTS |
|
VARCHAR2(4000) |
NULL |
| Name | Null? | Type | Value |
|---|---|---|---|
|
TABLE_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_TYPE |
|
VARCHAR2(11) |
"TABLE" or "VIEW" or "SYNONYM" |
| Name | Null? | Type | Value |
|---|---|---|---|
|
TABLE_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
COLUMN_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
COMMENTS |
|
VARCHAR2(4000) |
NULL |
| Name | Null? | Type | Value |
|---|---|---|---|
|
OWNER |
NOT NULL |
VARCHAR2(30) |
|
|
CONSTRAINT_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
COLUMN_NAME |
|
VARCHAR2(4000) |
|
|
POSITION |
|
NUMBER |
|
| Name | Null? | Type | Value |
|---|---|---|---|
|
INDEX_NAME |
|
VARCHAR2(30) |
|
|
TABLE_NAME |
|
VARCHAR2(30) |
|
|
COLUMN_NAME |
|
VARCHAR2(4000) |
|
|
COLUMN_POSITION |
|
NUMBER |
|
|
COLUMN_LENGTH |
|
NUMBER |
|
|
DESCEND |
|
VARCHAR2(4) |
"DESC" or "ASC" |
| Name | Null? | Type | Value |
|---|---|---|---|
|
TABLE_NAME |
NOT NULL |
VARCHAR2(30) |
|
|
TABLE_TYPE |
|
VARCHAR2(11) |
"TABLE" or "VIEW" |
|
COMMENTS |
|
VARCHAR2(4000) |
NULL |
|
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