Oracle® Database Gateway for ODBC

User's Guide

12c Release 1 (12.1)

E17936-05

July 2014

Oracle Database Gateway for ODBC User's Guide, 12c Release 1 (12.1)

E17936-05

Copyright © 2007, 2014, Oracle and/or its affiliates. All rights reserved.

Primary Author:  Maitreyee Chaliha

Contributor:  Vira Goorah, Juan Pablo Ahues-Vasquez, Peter Castro, Charles Benet, Peter Wong, and Govind Lakkoju

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List of Figures

1-1 Oracle and Non-Oracle Systems on Separate Machines

1-2 Oracle and Non-Oracle Systems on the Same Machine

List of Tables

A-1 Data Type Mapping and Restrictions

C-1 Oracle Database Gateway for ODBC Data Dictionary Mapping

C-2 ALL_CATALOG

C-3 ALL_COL_COMMENTS

C-4 ALL_CONS_COLUMNS

C-5 ALL_CONSTRAINTS

C-6 ALL_IND_COLUMNS

C-7 ALL_INDEXES

C-8 ALL_OBJECTS

C-9 ALL_TAB_COLUMNS

C-10 ALL_TAB_COMMENTS

C-11 ALL_TABLES

C-12 ALL_USERS

C-13 ALL_VIEWS

C-14 DICTIONARY

C-15 DICT_COLUMNS

C-16 USER_CATALOG

C-17 USER_COL_COMMENTS

C-18 USER_CONS_COLUMNS

C-19 USER_CONSTRAINTS

C-20 USER_IND_COLUMNS

C-21 USER_INDEXES

C-22 USER_OBJECTS

C-23 USER_TABCOLUMNS

C-24 USER_TAB_COMMENTS

C-25 USER_TABLES

C-26 USER_USERS

C-27 USER_VIEWS

Preface

This manual describes the Oracle Database Gateway for ODBC, which enables Oracle client applications to access non-Oracle systems data through Structured Query Language (SQL). The gateway, with the Oracle database, creates the appearance that all data resides on a local Oracle database, even though the data can be widely distributed.

This preface covers the following topics:

Audience

Documentation Accessibility

Related Documents

Conventions

Audience

This manual is intended for Oracle database administrators who perform the following tasks:

Installing and configuring the Oracle Database Gateway for ODBC

Diagnosing gateway errors

Using the gateway to access non-Oracle system data

Note:

You should understand the fundamentals of Oracle Database Gateways and the UNIX based platform before using this guide to install or administer the gateway.

Documentation Accessibility

For information about Oracle's commitment to accessibility, visit the Oracle Accessibility Program website at http://www.oracle.com/pls/topic/lookup?ctx=acc&id=docacc.

Access to Oracle Support

Oracle customers have access to electronic support through My Oracle Support. For information, visit http://www.oracle.com/pls/topic/lookup?ctx=acc&id=info or visit http://www.oracle.com/pls/topic/lookup?ctx=acc&id=trs if you are hearing impaired.

Related Documents

For more information, see the following documents:

Oracle Database New Features Guide

Oracle Call Interface Programmer's Guide

Oracle Database Administrator's Guide

Oracle Database Development Guide

Oracle Database Concepts

Oracle Database Performance Tuning Guide

Oracle Database Error Messages

Oracle Database Globalization Support Guide

Oracle Database Reference

Oracle Database SQL Language Reference

Oracle Database Net Services Administrator's Guide

SQL*Plus User's Guide and Reference

Oracle Database Heterogeneous Connectivity User's Guide

Oracle Database Security Guide

Many of the examples in this book use the sample schemas of the seed database, which is installed by default when you install Oracle. Refer to Oracle Database Sample Schemas for information on how these schemas were created and how you can use them yourself.

Conventions

The following text conventions are used in this document:

Convention | Meaning
boldface | Boldface type indicates graphical user interface elements associated with an action, or terms defined in text or the glossary.
italic | Italic type indicates book titles, emphasis, or placeholder variables for which you supply particular values.
monospace | Monospace type indicates commands within a paragraph, URLs, code in examples, text that appears on the screen, or text that you enter.

1 Introduction

This chapter introduces the challenge faced by organizations when running several different database systems. It briefly covers Heterogeneous Services, the technology that the Oracle Database Gateway for ODBC is based on.

To get a good understanding of generic gateway technology, Heterogeneous Services, and how Oracle Database Gateways fit in the picture, reading the Oracle Database Heterogeneous Connectivity User's Guide first is highly recommended.

This chapter contains the following sections:

Overview

Heterogeneous Services Technology

Oracle Database Gateway for ODBC

Oracle Database Gateway for ODBC Architecture

ODBC Connectivity Requirements

Overview

Heterogeneous data access is a problem that affects a lot of companies. A lot of companies run several different database systems. Each of these systems stores data and has a set of applications that run against it. Consolidation of this data in one database system is often hard - in large part because many of the applications that run against one database may not have an equivalent that runs against another. Until such time as migration to one consolidated database system is made feasible, it is necessary for the various heterogeneous database systems to interoperate.

Oracle Database Gateways provide the ability to transparently access data residing in a non-Oracle system from an Oracle environment. This transparency eliminates the need for application developers to customize their applications to access data from different non-Oracle systems, thus decreasing development efforts and increasing the mobility of the application. Applications can be developed using a consistent Oracle interface for both Oracle and non-Oracle systems.

Gateway technology is composed of two parts: a component that has the generic technology to connect to a non-Oracle system, which is common to all the non-Oracle systems, called Heterogeneous Services, and a component that is specific to the non-Oracle system that the gateway connects to. Heterogeneous Services, in conjunction with the Oracle Database Gateways, enable transparent access to non-Oracle systems from an Oracle environment.

Heterogeneous Services Technology

Heterogeneous Services provides the generic technology for connecting to non-Oracle systems. As an integrated component of the database, Heterogeneous Services can exploit features of the database, such as the powerful SQL parsing and distributed optimization capabilities.

Heterogeneous Services extend the Oracle SQL engine to recognize the SQL and procedural capabilities of the remote non-Oracle system and the mappings required to obtain necessary data dictionary information. Heterogeneous Services provides two types of translations: the ability to translate Oracle SQL into the proper dialect of the non-Oracle system as well as data dictionary translations that displays the metadata of the non-Oracle system in the local format. For situations where no translations are available, native SQL can be issued to the non-Oracle system using the pass-through feature of Heterogeneous Services.

Heterogeneous Services also maintains the transaction coordination between Oracle and the remote non-Oracle system.

See Also:

Oracle Database Heterogeneous Connectivity User's Guide for more information about Heterogeneous Services.

Oracle Database Gateway for ODBC

Oracle Database Gateway for ODBC is intended for low-end data integration solutions requiring the dynamic query capability to connect from an Oracle database to non-Oracle systems. Any data source compatible with the ODBC standards described in this chapter can be accessed using Oracle Database Gateway for ODBC.

The capabilities, SQL mappings, data type conversions, and interface to the remote non-Oracle system are contained in the gateway. The gateway interacts with Heterogeneous Services to provide the transparent connectivity between Oracle and non-Oracle systems.

Oracle Database Gateway for ODBC Architecture

To access the non-Oracle data store using Oracle Database Gateway for ODBC, the gateway works with an ODBC driver. The driver that you use must be on the same machine as the gateway. The non-Oracle system can reside on the same machine as the Oracle database or on a different machine.

The gateway can be installed on the machine running the non-Oracle system, the machine running the Oracle database or on a third machine as a standalone. Each configuration has its advantages and disadvantages. The issues to consider when determining where to install the gateway are network traffic, operating system platform availability, hardware resources and storage.

Note:

The ODBC driver may require non-Oracle client libraries even if the non-Oracle database is located on the same machine. Refer to your ODBC driver documentation for information about the requirements for the ODBC driver.

Oracle and Non-Oracle Systems on Separate Machines

Figure 1-1 shows an example of a configuration in which an Oracle and non-Oracle database are on separate machines, communicating through Oracle Database Gateway for ODBC. The client connects to the non-Oracle system through a network.

Figure 1-1 Oracle and Non-Oracle Systems on Separate Machines

In this configuration:

A client connects to the Oracle database through Oracle Net.

The Heterogeneous Services component of the Oracle database connects through Oracle Net to the gateway.

The gateway communicates with the following non-Oracle components:

An ODBC driver manager

An ODBC driver

Each user session receives its own dedicated agent process spawned by the first use in that user session of the database link to the non-Oracle system. The agent process ends when the user session ends.

Note:

The ODBC driver may require non-Oracle client libraries even if the non-Oracle database is located on the same machine. Refer to your ODBC driver documentation for information about the requirements for the ODBC driver.

Oracle and Non-Oracle Systems on the Same Machine

Figure 1-2 shows an example of a configuration in which an Oracle and non-Oracle database are on the same machine, again communicating through Oracle Database Gateway for ODBC.

Figure 1-2 Oracle and Non-Oracle Systems on the Same Machine

In this configuration:

A client connects to the Oracle database through Oracle Net.

The Heterogeneous Services component of the Oracle database connects through Oracle Net to the gateway

The agent communicates with the following non-Oracle components:

An ODBC driver manager

An ODBC driver

The driver then allows access to the non-Oracle data store.

Each user session receives its own dedicated agent process spawned by the first use in that user session of the database link to the non-Oracle system. The agent process ends when the user session ends.

Note:

The ODBC driver may require non-Oracle client libraries even if the non-Oracle database is located on the same machine. Refer to your ODBC driver documentation for information about the requirements for the ODBC driver.

ODBC Connectivity Requirements

To use Oracle Database Gateway for ODBC, you must have an ODBC driver installed on the same machine as the gateway. The ODBC driver manager and driver must meet the following requirements:

The following ODBC catalog functions must work inside a transaction:

SQLColumns

SQLForeignKeys

SQLGetFunctions

SQLGetInfo

SQLGetTypeInfo

SQLPrimaryKeys

SQLProcedureColumns

SQLProcedures

SQLStatistics

SQLTables

On Windows:

The ODBC driver must have compliance level to ODBC standard 3.0. For multi-byte support, the driver needs to meet ODBC standard 3.5.

The ODBC driver and driver manager must conform to ODBC application program interface (API) conformance Level 1 or higher. If the ODBC driver or driver manager does not support multiple active ODBC cursors, the complexity of SQL statements that you can execute using Oracle Database Gateway for ODBC is restricted.

On UNIX:

The ODBC driver manager must be installed on the same machine.

The ODBC driver must have compliance level to ODBC Standard 3.0 and have a conformance level 1 or higher. If the ODBC driver works with an ODBC driver manager, the ODBC driver manager must be compliant with ODBC Standard 3.0 or higher. The ODBC driver must have compliance level to ODBC standard 3.0. For multi-byte support, the driver needs to meet ODBC standard 3.5.

See Also:

Your ODBC driver documentation for dependencies on an ODBC driver manager, and Oracle Database Concepts for more information on transaction isolation levels.

The ODBC driver you use must support all of the core SQL ODBC data types and must support SQL grammar level SQL_92. The ODBC driver should also expose the following ODBC APIs:

SQLAllocHandle

SQLBindCol

SQLBindParameter

SQLCancel

SQLColAttribute

SQLColumns

SQLConnect

SQLDescribeCol

SQLDisconnect

SQLDriverConnect

SQLEndTran

SQLExecDirect

SQLExecute

SQLFetch

SQLForeignKeys

SQLFreeHandle

SQLFreeStmt

SQLGetConnectAttr

SQLGetData

SQLGetDiagField

SQLGetDiagRec

SQLGetEnvAttr

SQLGetFunctions

SQLGetInfo

SQLGetStmtAttr

SQLGetTypeInfo

SQLMoreResults

SQLNumResultCols

SQLParamData

SQLPrepare

SQLPrimaryKeys

SQLProcedureColumns

SQLProcedures

SQLPutData

SQLRowCount

SQLSetConnectAttr

SQLSetEnvAttr

SQLSetDescField

SQLSetDescRec

SQLSetStmtAttr

SQLStatistics - If statistics are to be supported

SQLTables

2 Oracle Database Gateway for ODBC Features and Restrictions

After the gateway is installed and configured, you can use the gateway to access data in non-Oracle systems, pass native commands from applications to the non-Oracle system, perform distributed queries, and copy data.

This chapter contains the following sections:

Using the Pass-Through Feature

AUTO COMMIT

Known Restrictions

Known Problems

Using the Pass-Through Feature

The gateway can pass native commands or statements from the application to the non-Oracle system using the DBMS_HS_PASSTHROUGH package.

Use the DBMS_HS_PASSTHROUGH package in a PL/SQL block to specify the statement to be passed to the non-Oracle system, as follows:

DECLARE
    num_rows INTEGER;
BEGIN
    num_rows := DBMS_HS_PASSTHROUGH.EXECUTE_IMMEDIATE@SYBS('command');
END;
/

Where command cannot be one of the following:

BEGIN TRANSACTION

COMMIT

ROLLBACK

SAVE

SHUTDOWN

The DBMS_HS_PASSTHROUGH package supports passing bind values and executing SELECT statements.

Note:

TRUNCATE cannot be used in a pass-through statement.

Note:

As a general rule it is recommended that you COMMIT after each DDL statement in the pass-through especially when going to a Sybase database.

See Also:

Oracle Database PL/SQL Packages and Types Reference and Chapter 3 of Oracle Database Heterogeneous Connectivity User's Guide for more information about the DBMS_HS_PASSTHROUGH package.

AUTO COMMIT

Some non-Oracle databases operate without logging. If read-only capability is desired under such environment, you need to set HS_TRANSACTION_MODEL=READ_ONLY_AUTOCOMMIT gateway parameter.

However, if you still need to have update capability, then set HS_TRANSACTION_MODEL=SINGLE_SITE_AUTOCOMMIT in the gateway initialization parameter file. Any update is committed immediately. Commit-confirm is not allowed for the targets operating without logging.

Known Restrictions

If you encounter incompatibility problems not listed in this section or in "Known Problems", contact Oracle Support Services. The following section describes the known restrictions:

BLOB and CLOB data cannot be read by pass-through queries

Updates or deletes that include unsupported functions within a WHERE clause are not allowed

Does not support stored procedures

Cannot participate in distributed transactions; they support single-site transactions only

Does not support multithreaded agents

Does not support updating LONG columns with bind variables

Does not support rowids

COMMIT or ROLLBACK in PL/SQL Cursor Loops Closes Open Cursors

SQL Syntax

COMMIT or ROLLBACK in PL/SQL Cursor Loops Closes Open Cursors

Any COMMIT or ROLLBACK issued in a PL/SQL cursor loop closes all open cursors, which can result in the following error:

ORA-1002:  fetch out of sequence

To prevent this error, move the COMMIT or ROLLBACK statement outside the cursor loop.

SQL Syntax

This section lists restrictions on the following SQL syntax:

WHERE CURRENT OF Clause

CONNECT BY Clause

ROWID

EXPLAIN PLAN Statement

WHERE CURRENT OF Clause

UPDATE and DELETE statements with the WHERE CURRENT OF clause are not supported by the gateway because they rely on the Oracle ROWID implementation. To update or delete a specific row through the gateway, a condition style WHERE clause must be used.

CONNECT BY Clause

The gateway does not support the CONNECT BY clause in a SELECT statement.

ROWID

The Oracle ROWID implementation is not supported.

EXPLAIN PLAN Statement

The EXPLAIN PLAN statement is not supported.

SQL*Plus COPY Command with Lowercase Table Names

You need to use double quotes to wrap around lowercase table names.

For example:

copy from tkhouser/tkhouser@inst1 insert loc_tkhodept using select * from "tkhodept"@holink2;

Database Links

The gateway is not multithreaded and cannot support shared database links. Each gateway session spawns a separate gateway process and connections cannot be shared.

See Also:

Appendix B, "Supported SQL Syntax and Functions" for more information about restrictions on SQL syntax.

Does not support CALLBACK links

Oracle Database Gateway for ODBC does not support CALLBACK links. Trying a CALLBACK link with the gateway will return the following error message:

ORA-02025: All tables in the SQL statement must be at the remote database

Known Problems

This section describes known problems and includes suggestions for correcting them when possible. If you have any questions or concerns about the problems, contact Oracle Support Services.

The following known problems are described in this section:

Encrypted Format Login

Date Arithmetic

Encrypted Format Login

Oracle database no longer supports the initialization parameter DBLINK_ENCRYPT_LOGIN. Up to version 7.3, this parameter's default TRUE value prevented the password for the login user ID from being sent over the network (in the clear). Later versions automatically encrypt the password.

Date Arithmetic

The following SQL expressions do not function correctly with the gateway:

date + number
number + date
date - number
date1 - date2

Statements with the preceding expressions are sent to the non-Oracle system without any translation. If the non-Oracle system does not support these date arithmetic functions, then the statements return an error.

A Data Type Conversion

Oracle maps ODBC data types to supported Oracle data types. When the results of a query are returned, Oracle converts the ODBC data types to Oracle data types.

The tables in this appendix show how Oracle maps ODBC data types to supported Oracle data types when it is retrieving data from a non-Oracle system.

This appendix contains the following table:

Table A-1, "Data Type Mapping and Restrictions"

Mapping ODBC Data Types to Oracle Data Types

The Oracle Database Gateway for ODBC maps the data types used in ODBC-compliant data sources to supported Oracle data types. When the results of a query are returned, the Oracle database converts the ODBC data types to Oracle data types. For example, the ODBC data type SQL_TYPE_TIMESTAMP is converted to Oracle's DATE data type.

If a table contains a column whose data type is not supported by Oracle Database Gateway for ODBC, the column information is not returned to the Oracle database.

Table A-1 maps ODBC data types into Oracle data types.

Table A-1 Data Type Mapping and Restrictions

ODBC
Oracle
Criteria
If Oracle uses large varchar (32k)

SQL_BIGINT

NUMBER(19,0)

-

SQL_BINARY

RAW

-

SQL_CHAR

CHAR

-

SQL_DECIMAL(p,s)

NUMBER(p,s)

-

SQL_DOUBLE

FLOAT(53)

-

SQL_FLOAT

FLOAT(53)

-

SQL_INTEGER

NUMBER(10)

Note: It is possible under some circumstance for the INTEGER ANSI data type to map to Precision 38, but it usually maps to Precision 10.

-

SQL_INTERVAL_YEAR

INTERVAL_YEAR_TO_MONTH

-

SQL_INTERVAL_MONTH

INTERVAL_YEAR_TO_MONTH

-

SQL_INTERVAL_YEAR_TO_MONTH

INTERVAL_YEAR_TO_MONTH

-

SQL_INTERVAL_DAY

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_HOUR

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_MINUTE

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_SECOND

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_DAY_TO_HOUR

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_DAY_TO_MINUTE

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_DAY_TO_SECOND

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_HOUR_TO_MINUTE

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_HOUR_TO_SECOND

INTERVAL_DAY_TO_SECOND

-

SQL_INTERVAL_MINUTE_TO_SECOND

INTERVAL_DAY_TO_SECOND

-

SQL_LONGVARBINARY

LONG RAW

-

SQL_LONGVARCHAR

LONG

Note: If an ANSI SQL implementation defines a large value for the maximum length of VARCHAR data, it is possible that ANSI VARCHAR will map to SQL_LONGVARCHAR and Oracle LONG.

4000 < N < = 32740

N <= 32767

SQL_NUMERIC(p[,s])

NUMBER(p[,s])

-

SQL_REAL

FLOAT(24)

-

SQL_SMALLINT

NUMBER(5)

-

SQL_TYPE_TIME

CHAR(15)

-

SQL_TINYINT

NUMBER(3)

-

SQL_TYPE_DATE

DATE

-

SQL_TYPE_TIMESTAMP

DATE

-

SQL_VARBINARY

RAW

-

SQL_VARCHAR

VARCHAR2

N < = 4000

N <= 32767

SQL_WCHAR

NCHAR

-

SQL_WVARCHAR

NVARCHAR

-

SQL_WLONGVARCHAR

LONG

if Oracle DB Character Set = Unicode. Otherwise, it is not supported

SQL_BIT

NUMBER(3)

-

B Supported SQL Syntax and Functions

This appendix contains the following sections:

Supported SQL Statements

Oracle Functions

Supported SQL Statements

Oracle Database Gateway for ODBC supports the following statements, but only if the ODBC driver and non-Oracle system can execute them and if the statements contain supported Oracle SQL functions:

DELETE

INSERT

SELECT

UPDATE

With a few exceptions, the gateway provides full support for Oracle DELETE, INSERT, SELECT, and UPDATE statements.

The gateway does not support Oracle data definition language (DDL) statements. No form of the Oracle ALTER, CREATE, DROP, GRANT, or TRUNCATE statements can be used. Instead, for ALTER, CREATE, DROP, and GRANT statements, use the pass-through feature of the gateway if you need to use DDL statements against the non-Oracle system database.

Note:

TRUNCATE cannot be used in a pass-through statement.

See Also:

Oracle Database SQL Language Reference for detailed descriptions of keywords, parameters, and options.

DELETE

The DELETE statement is fully supported. However, only Oracle functions supported by the non-Oracle system can be used.

INSERT

The INSERT statement is fully supported. However, only Oracle functions supported by the non-Oracle system can be used.

SELECT

The SELECT statement is fully supported, with these exceptions:

CONNECT BY condition

NOWAIT

START WITH condition

WHERE CURRENT OF

UPDATE

The UPDATE statement is fully supported. However, only Oracle functions supported by the non-Oracle system can be used. Also, you cannot have SQL statements in the subquery that refer to the same table name in the outer query. Subqueries are not supported in the SET clause.

Oracle Functions

All functions are evaluated by the non-Oracle system after the gateway has converted them to the native SQL. Only a limited set of functions are assumed to be supported by the non-Oracle system. Most Oracle functions have no equivalent function in this limited set. Consequently, although post-processing is performed by the Oracle database, Oracle Database Gateway for ODBC does not support many Oracle functions, possibly impacting performance.

If an Oracle SQL function is not supported by Oracle Database Gateway for ODBC, this function is not supported in DELETE, INSERT, or UPDATE statements. In SELECT statements, these functions are evaluated by the Oracle database and processed after they are returned from the non-Oracle system.

If an unsupported function is used in a DELETE, INSERT, or UPDATE statement, it generates the following Oracle error:

ORA-02070: database db_link_name does not support function in this context

Oracle Database Gateway for ODBC assumes that ODBC driver provider that is being used supports the following minimum set of SQL functions:

AVG(exp)

LIKE(exp)

COUNT(*)

MAX(exp)

MIN(exp)

NOT

C Data Dictionary

Data dictionary information is stored in the non-Oracle system as system tables and is accessed through ODBC application programming interfaces (APIs). This appendix documents data dictionary translation support. It explains how to access non-Oracle data dictionaries, describes how to use supported views and tables, and explains data dictionary mapping.

This appendix contains the following topics:

Accessing the Non-Oracle Data Dictionary

Views and Tables Supported by Oracle Database Gateway for ODBC

Accessing the Non-Oracle Data Dictionary

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 Oracle 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 agent:

Maps the requested table, view, or synonym to one or more ODBC APIs (see Data Dictionary Mapping). The agent translates all data dictionary column names to their corresponding non-Oracle column names within the query.

Sends the sequence of APIs to the non-Oracle system.

Possibly converts the retrieved non-Oracle data to give it the appearance of the Oracle data dictionary table.

Passes the data dictionary information from the non-Oracle system table to Oracle.

Note:

The values returned when querying the Oracle Database Gateway for ODBC data dictionary may not be the same as those returned by the Oracle SQL*Plus DESCRIBE command.

Views and Tables Supported by Oracle Database Gateway for ODBC

Oracle Database Gateway for ODBC supports only the views and tables shown in Table C-1.

If you use an unsupported view, you receive an Oracle error message stating no rows were 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 Oracle Database Gateway for ODBC, 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.

Data Dictionary Mapping

The tables in this section list Oracle data dictionary view names and the equivalent ODBC APIs used. Table C-1 shows a list of all Oracle data dictionary view names supported by Oracle Database Gateway for ODBC.

Table C-1 Oracle Database Gateway for ODBC Data Dictionary Mapping

View
ODBC API

ALL_CATALOG

SQLTables

ALL_COL_COMMENTS

SQLColumns

ALL_CONS_COLUMNS

SQLPrimaryKeys, SQLForeignKeys

ALL_CONSTRAINTS

SQLPrimaryKeys, SQLForeignKeys

ALL_IND_COLUMNS

SQLStatistics

ALL_INDEXES

SQLStatistics

ALL_OBJECTS

SQLTables, SQLProcedures, SQLStatistics

ALL_TAB_COLUMNS

SQLColumns

ALL_TAB_COMMENTS

SQLTables

ALL_TABLES

SQLStatistics

ALL_USERS

SQLTables

ALL_VIEWS

SQLTables

DICTIONARY

SQLTables

DICT_COLUMNS

SQLTables

USER_COL_COMMENTS

SQLColumns

USER_CONS_COLUMNS

SQLPrimaryKeys, SQLForeignKeys

USER_CONSTRAINTS

SQLPrimaryKeys, SQLForeignKeys

USER_IND_COLUMNS

SQLStatistics

USER_INDEXES

SQLStatistics

USER_OBJECTS

SQLTables, SQLProcedures, SQLStatistics

USER_TABCOLUMNS

SQLColumns

USER_TAB_COMMENTS

SQLTables

USER_TABLES

SQLStatistics

USER_USERS

SQLTables

USER_VIEWS

SQLTables

Oracle Database Gateway for ODBC Data Dictionary Descriptions

The Oracle Database Gateway for ODBC data dictionary tables and views provide the following information:

Name, data type, and width of each column

The contents of columns with fixed values

In the descriptions that follow, the values in the Null? column may differ from the Oracle data dictionary tables and views. Any default value is shown to the right of an item.

Table C-2 ALL_CATALOG

Name
Type
Value

OWNER

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

TABLE_TYPE

VARCHAR2(11)

"TABLE" or "VIEW" or "SYNONYM"

Table C-3 ALL_COL_COMMENTS

Name
Type
Value

OWNER

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

COLUMN_NAME

VARCHAR2(30)

-

COMMENTS

VARCHAR2(4000)

NULL

Table C-4 ALL_CONS_COLUMNS

Name
Type
Value

OWNER

VARCHAR2(30)

-

CONSTRAINT_NAME

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

COLUMN_NAME

VARCHAR2(4000)

-

POSITION

NUMBER

-

Table C-5 ALL_CONSTRAINTS

Name
Type
Value

OWNER

VARCHAR2(30)

-

CONSTRAINT_NAME

VARCHAR2(30)

-

CONSTRAINT_TYPE

VARCHAR2(1)

"R" or "P"

TABLE_NAME

VARCHAR2(30)

-

SEARCH_CONDITION

LONG

NULL

R_OWNER

VARCHAR2(30)

-

R_CONSTRAINT_NAME

VARCHAR2(30)

-

DELETE_RULE

VARCHAR2(9)

"CASCADE" or "NO ACTION" or "SET NULL"

STATUS

VARCHAR2(8)

NULL

DEFERRABLE

VARCHAR2(14)

NULL

DEFERRED

VARCHAR2(9)

NULL

VALIDATED

VARCHAR2(13)

NULL

GENERATED

VARCHAR2(14)

NULL

BAD

VARCHAR2(3)

NULL

RELY

VARCHAR2(4)

NULL

LAST_CHANGE

DATE

NULL

Table C-6 ALL_IND_COLUMNS

Name
Type
Value

INDEX_OWNER

VARCHAR2(30)

-

INDEX_NAME

VARCHAR2(30)

-

TABLE_OWNER

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

COLUMN_NAME

VARCHAR2(4000)

-

COLUMN_POSITION

NUMBER

-

COLUMN_LENGTH

NUMBER

-

DESCEND

VARCHAR2(4)

"DESC" or "ASC"

Table C-7 ALL_INDEXES

Name
Type
Value

OWNER

VARCHAR2(30)

-

INDEX_NAME

VARCHAR2(30)

-

INDEX_TYPE

VARCHAR2(27)

NULL

TABLE_OWNER

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

TABLE_TYPE

CHAR(5)

"TABLE"

UNIQUENESS

VARCHAR2(9)

"UNIQUE" or "NONUNIQUE"

COMPRESSION

VARCHAR2(8)

NULL

PREFIX_LENGTH

NUMBER

0

TABLESPACE_NAME

VARCHAR2(30)

NULL

INI_TRANS

NUMBER

0

MAX_TRANS

NUMBER

0

INITIAL_EXTENT

NUMBER

0

NEXT_EXTENT

NUMBER

0

MIN_EXTENTS

NUMBER

0

MAX_EXTENTS

NUMBER

0

PCT_INCREASE

NUMBER

0

PCT_THRESHOLD

NUMBER

0

INCLUDE_COLUMNS

NUMBER

0

FREELISTS

NUMBER

0

FREELIST_GROUPS

NUMBER

0

PCT_FREE

NUMBER

0

LOGGING

VARCHAR2(3)

NULL

BLEVEL

NUMBER

0

LEAF_BLOCKS

NUMBER

0

DISTINCT_KEYS

NUMBER

AVG_LEAF_BLOCKS_PER_KEY

NUMBER

0

AVG_DATA_BLOCKS_PER_KEY

NUMBER

0

CLUSTERING_FACTOR

NUMBER

0

STATUS

VARCHAR2(8)

NULL

NUM_ROWS

NUMBER

0

SAMPLE_SIZE

NUMBER

0

LAST_ANALYZED

DATE

NULL

DEGREE

VARCHAR2(40)

NULL

INSTANCES

VARCHAR2(40)

NULL

PARTITIONED

VARCHAR2(3)

NULL

TEMPORARY

VARCHAR2(1)

NULL

GENERATED

VARCHAR2(1)

NULL

SECONDARY

VARCHAR2(1)

NULL

BUFFER_POOL

VARCHAR2(7)

NULL

USER_STATS

VARCHAR2(3)

NULL

DURATION

VARCHAR2(15)

NULL

PCT_DIRECT_ACCESS

NUMBER

0

ITYP_OWNER

VARCHAR2(30)

NULL

ITYP_NAME

VARCHAR2(30)

NULL

PARAMETERS

VARCHAR2(1000)

NULL

GLOBAL_STATS

VARCHAR2(3)

NULL

DOMIDX_STATUS

VARCHAR2(12)

NULL

DOMIDX_OPSTATUS

VARCHAR2(6)

NULL

FUNCIDX_STATUS

VARCHAR2(8)

NULL

Table C-8 ALL_OBJECTS

Name
Type
Value

OWNER

VARCHAR2(30)

-

OBJECT_NAME

VARCHAR2(30)

-

SUBOBJECT_NAME

VARCHAR2(30)

NULL

OBJECT_ID

NUMBER

0

DATA_OBJECT_ID

NUMBER

0

OBJECT_TYPE

VARCHAR2(18)

"TABLE" or "VIEW" or "SYNONYM" or "INDEX" or "PROCEDURE"

CREATED

DATE

NULL

LAST_DDL_TIME

DATE

NULL

TIMESTAMP

VARCHAR2(19)

NULL

STATUS

VARCHAR2(7)

NULL

TEMPORARY

VARCHAR2(1)

NULL

GENERATED

VARCHAR2(1)

NULL

SECONDARY

VARCHAR2(1)

NULL

Table C-9 ALL_TAB_COLUMNS

Name
Type
Value

OWNER

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

COLUMN_NAME

VARCHAR2(30)

-

DATA_TYPE

VARCHAR2(106)

-

DATA_TYPE_MOD

VARCHAR2(3)

NULL

DATA_TYPE_OWNER

VARCHAR2(30)

NULL

DATA_LENGTH

NUMBER

-

DATA_PRECISION

NUMBER

-

DATA_SCALE

NUMBER

-

NULLABLE

VARCHAR2(1)

"Y" or "N"

COLUMN_ID

NUMBER

-

DEFAULT_LENGTH

NUMBER

0

DATA_DEFAULT

LONG

NULL

NUM_DISTINCT

NUMBER

0

LOW_VALUE

RAW(32)

NULL

HIGH_VALUE

RAW(32)

NULL

DENSITY

NUMBER

0

NUM_NULLS

NUMBER

0

NUM_BUCKETS

NUMBER

0

LAST_ANALYZED

DATE

NULL

SAMPLE_SIZE

NUMBER

0

CHARACTER_SET_NAME

VARCHAR2(44)

NULL

CHAR_COL_DEC_LENGTH

NUMBER

0

GLOBAL_STATS

VARCHAR2(3)

NULL

USER_STATS

VARCHAR2(3)

NULL

AVG_COL_LEN

NUMBER

0

Table C-10 ALL_TAB_COMMENTS

Name
Type
Value

OWNER

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

TABLE_TYPE

VARCHAR2(11)

"TABLE" or "VIEW"

COMMENTS

VARCHAR2(4000)

NULL

Table C-11 ALL_TABLES

Name
Type
Value

OWNER

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

TABLESPACE_NAME

VARCHAR2(30)

NULL

CLUSTER_NAME

VARCHAR2(30)

NULL

IOT_NAME

VARCHAR2(30)

NULL

PCT_FREE

NUMBER

0

PCT_USED

NUMBER

0

INI_TRANS

NUMBER

0

MAX_TRANS

NUMBER

0

INITIAL_EXTENT

NUMBER

0

NEXT_EXTENT

NUMBER

0

MIN_EXTENTS

NUMBER

0

MAX_EXTENTS

NUMBER

0

PCT_INCREASE

NUMBER

0

FREELISTS

NUMBER

0

FREELIST_GROUPS

NUMBER

0

LOGGING

VARCHAR2(3)

NULL

BACKED_UP

VARCHAR2(1)

NULL

NUM_ROWS

NUMBER

-

BLOCKS

NUMBER

-

EMPTY_BLOCKS

NUMBER

0

AVG_SPACE

NUMBER

0

CHAIN_CNT

NUMBER

0

AVG_ROW_LEN

NUMBER

0

AVG_SPACE_FREELIST_BLOCKS

NUMBER

0

NUM_FREELIST_BLOCKS

NUMBER

0

DEGREE

VARCHAR2(10)

NULL

INSTANCES

VARCHAR2(10)

NULL

CACHE

VARCHAR2(5)

NULL

TABLE_LOCK

VARCHAR2(8)

NULL

SAMPLE_SIZE

NUMBER

0

LAST_ANALYZED

DATE

NULL

PARTITIONED

VARCHAR2(3)

NULL

IOT_TYPE

VARCHAR2(12)

NULL

TEMPORARY

VARCHAR2(1)

NULL

SECONDARY

VARCHAR2(1)

NULL

NESTED

VARCHAR2(3)

NULL

BUFFER_POOL

VARCHAR2(7)

NULL

ROW_MOVEMENT

VARCHAR2(8)

NULL

GLOBAL_STATS

VARCHAR2(3)

NULL

USER_STATS

VARCHAR2(3)

NULL

DURATION

VARHCAR2(15)

NULL

SKIP_CORRUPT

VARCHAR2(8)

NULL

MONITORING

VARCHAR2(3)

NULL

Table C-12 ALL_USERS

Name
Type
Value

USERNAME

VARCHAR2(30)

-

USER_ID

NUMBER

0

CREATED

DATE

NULL

Table C-13 ALL_VIEWS

Name
Type
Value

OWNER

VARCHAR2(30)

-

VIEW_NAME

VARCHAR2(30)

-

TEXT_LENGTH

NUMBER

0

TEXT

LONG

NULL

TYPE_TEXT_LENGTH

NUMBER

0

TYPE_TEXT

VARCHAR2(4000)

NULL

OID_TEXT_LENGTH

NUMBER

0

OID_TEXT

VARCHAR2(4000)

NULL

VIEW_TYPE_OWNER

VARCHAR2(30)

NULL

VIEW_TYPE

VARCHAR2(30)

NULL

Table C-14 DICTIONARY

Name
Type
Value

TABLE_NAME

VARCHAR2(30)

-

COMMENTS

VARCHAR2(4000)

NULL

Table C-15 DICT_COLUMNS

Name
Type
Value

TABLE_NAME

VARCHAR2(30)

-

COLUMN_NAME

VARCHAR2(30)

-

COMMENTS

VARCHAR2(4000)

NULL

Table C-16 USER_CATALOG

Name
Type
Value

TABLE_NAME

VARCHAR2(30)

-

TABLE_TYPE

VARCHAR2(11)

"TABLE" or, "VIEW" or "SYNONYM"

Table C-17 USER_COL_COMMENTS

Name
Type
Value

TABLE_NAME

VARCHAR2(30)

-

COLUMN_NAME

VARCHAR2(30)

-

COMMENTS

VARCHAR2(4000)

NULL

Table C-18 USER_CONS_COLUMNS

Name
Type
Value

OWNER

VARCHAR2(30)

-

CONSTRAINT_NAME

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

COLUMN_NAME

VARCHAR2(4000)

-

POSITION

NUMBER

-

Table C-19 USER_CONSTRAINTS

Name
Type
Value

OWNER

VARCHAR2(30)

-

CONSTRAINT_NAME

VARCHAR2(30)

-

CONSTRAINT_TYPE

VARCHAR2(1)

R or P

TABLE_NAME

VARCHAR2(30)

-

SEARCH_CONDITION

LONG

NULL

R_OWNER

VARCHAR2(30)

-

R_CONSTRAINT_NAME

VARCHAR2(30)

-

DELETE_RULE

VARCHAR2(9)

"CASCADE" or "NO ACTION" or "SET NULL"

STATUS

VARCHAR2(8)

NULL

DEFERRABLE

VARCHAR2(14)

NULL

DEFERRED

VARCHAR2(9)

NULL

VALIDATED

VARCHAR2(13)

NULL

GENERATED

VARCHAR2(14)

NULL

BAD

VARCHAR2(3)

NULL

RELY

VARCHAR2(4)

NULL

LAST_CHANGE

DATE

NULL

Table C-20 USER_IND_COLUMNS

Name
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"

Table C-21 USER_INDEXES

Name
Type
Value

INDEX_NAME

VARCHAR2(30)

-

INDEX_TYPE

VARCHAR2(27)

NULL

TABLE_OWNER

VARCHAR2(30)

-

TABLE_NAME

VARCHAR2(30)

-

TABLE_TYPE

VARCHAR2(11)

"TABLE"

UNIQUENESS

VARCHAR2(9)

"UNIQUE" or "NONUNIQUE"

COMPRESSION

VARCHAR2(8)

NULL

PREFIX_LENGTH

NUMBER

0

TABLESPACE_NAME

VARCHAR2(30)

NULL

INI_TRANS

NUMBER

0

MAX_TRANS

NUMBER

0

INITIAL_EXTENT

NUMBER

0

NEXT_EXTENT

NUMBER

0

MIN_EXTENTS

NUMBER

0

MAX_EXTENTS

NUMBER

0

PCT_INCREASE

NUMBER

0

PCT_THRESHOLD

NUMBER

0

INCLUDE_COLUMNS

NUMBER

0

FREELISTS

NUMBER

0

FREELIST_GROUPS

NUMBER

0

PCT_FREE

NUMBER

0

LOGGING

VARCHAR2(3)

NULL

BLEVEL

NUMBER

0

LEAF_BLOCKS

NUMBER

0

DISTINCT_KEYS

NUMBER

-

AVG_LEAF_BLOCKS_PER_KEY

NUMBER

0

AVG_DATA_BLOCKS_PER_KEY

NUMBER

0

CLUSTERING_FACTOR

NUMBER

0

STATUS

VARCHAR2(8)

NULL

NUM_ROWS

NUMBER

0

SAMPLE_SIZE

NUMBER

0

LAST_ANALYZED

DATE

NULL

DEGREE

VARCHAR2(40)

NULL

INSTANCES

VARCHAR2(40)

NULL

PARTITIONED

VARCHAR2(3)

NULL

TEMPORARY

VARCHAR2(1)

NULL

GENERATED

VARCHAR2(1)

NULL

SECONDARY

VARCHAR2(1)

NULL

BUFFER_POOL

VARCHAR2(7)

NULL

USER_STATS

VARCHAR2(3)

NULL

DURATION

VARHCAR2(15)

NULL

PCT_DIRECT_ACCESS

NUMBER

0

ITYP_OWNER

VARCHAR2(30)

NULL

ITYP_NAME

VARCHAR2(30)

NULL

PARAMETERS

VARCHAR2(1000)

NULL

GLOBAL_STATS

VARCHAR2(3)

NULL

DOMIDX_STATUS

VARCHAR2(12)

NULL

DOMIDX_OPSTATUS

VARCHAR2(6)

NULL

FUNCIDX_STATUS

VARCHAR2(8)

NULL

Table C-22 USER_OBJECTS

Name
Type
Value

OBJECT_NAME

VARCHAR2(128)

-

SUBOBJECT_NAME

VARCHAR2(30)

NULL

OBJECT_ID

NUMBER

0

DATA_OBJECT_ID

NUMBER

0

OBJECT_TYPE

VARCHAR2(18)

"TABLE" or "VIEW" or "SYNONYM" or "INDEX" or "PROCEDURE"

CREATED

DATE

NULL

LAST_DDL_TIME

DATE

NULL

TIMESTAMP

VARCHAR2(19)

NULL

STATUS

VARCHAR2(7)

NULL

TEMPORARY

VARCHAR2(1)

NULL

GENERATED

VARCHAR2(1)

NULL

SECONDARY

VARCHAR2(1)

NULL

Table C-23 USER_TABCOLUMNS

Name
Type
Value

TABLE_NAME

VARCHAR2(30)

-

COLUMN_NAME

VARCHAR2(30)

-

DATA_TYPE

VARCHAR2(106)

-

DATA_TYPE_MOD

VARCHAR2(3)

NULL

DATA_TYPE_OWNER

VARCHAR2(30)

NULL

DATA_LENGTH

NUMBER

-

DATA_PRECISION

NUMBER

-

DATA_SCALE

NUMBER

-

NULLABLE

VARCHAR2(1)

"Y" or "N"

COLUMN_ID

NUMBER

-

DEFAULT_LENGTH

NUMBER

NULL

DATA_DEFAULT

LONG

NULL

NUM_DISTINCT

NUMBER

NULL

LOW_VALUE

RAW(32)

NULL

HIGH_VALUE

RAW(32)

NULL

DENSITY

NUMBER

0

NUM_NULLS

NUMBER

0

NUM_BUCKETS

NUMBER

0

LAST_ANALYZED

DATE

NULL

SAMPLE_SIZE

NUMBER

0

CHARACTER_SET_NAME

VARCHAR2(44)

NULL

CHAR_COL_DECL_LENGTH

NUMBER

0

GLOBAL_STATS

VARCHAR2(3)

NULL

USER_STATS

VARCHAR2(3)

NULL

AVG_COL_LEN

NUMBER

0

Table C-24 USER_TAB_COMMENTS

Name
Type
Value

TABLE_NAME

VARCHAR2(30)

-

TABLE_TYPE

VARCHAR2(11)

"TABLE" or "VIEW"

COMMENTS

VARCHAR2(4000)

NULL

Table C-25 USER_TABLES

Name
Type
Value

TABLE_NAME

VARCHAR2(30)

-

TABLESPACE_NAME

VARCHAR2(30)

NULL

CLUSTER_NAME

VARCHAR2(30)

NULL

IOT_NAME

VARCHAR2(30)

NULL

PCT_FREE

NUMBER

0

PCT_USED

NUMBER

0

INI_TRANS

NUMBER

0

MAX_TRANS

NUMBER

0

INITIAL_EXTENT

NUMBER

0

NEXT_EXTENT

NUMBER

0

MIN_EXTENTS

NUMBER

0

MAX_EXTENTS

NUMBER

0

PCT_INCREASE

NUMBER

0

FREELISTS

NUMBER

0

FREELIST_GROUPS

NUMBER

0

LOGGING

VARCHAR2(3)

NULL

BACKED_UP

VARCHAR2(1)

NULL

NUM_ROWS

NUMBER

-

BLOCKS

NUMBER

-

EMPTY_BLOCKS

NUMBER

0

AVG_SPACE

NUMBER

0

CHAIN_CNT

NUMBER

0

AVG_ROW_LEN

NUMBER

0

AVG_SPACE_FREELIST_BLOCKS

NUMBER

0

NUM_FREELIST_BLOCKS

NUMBER

0

DEGREE

VARCHAR2(10)

NULL

INSTANCES

VARCHAR2(10)

NULL

CACHE

VARCHAR2(5)

NULL

TABLE_LOCK

VARCHAR2(8)

NULL

SAMPLE_SIZE

NUMBER

0

LAST_ANALYZED

DATE

NULL

PARTITIONED

VARCHAR2(3)

NULL

IOT_TYPE

VARCHAR2(12)

NULL

TEMPORARY

VARHCAR2(1)

NULL

SECONDARY

VARCHAR2(1)

NULL

NESTED

VARCHAR2(3)

NULL

BUFFER_POOL

VARCHAR2(7)

NULL

ROW_MOVEMENT

VARCHAR2(8)

NULL

GLOBAL_STATS

VARCHAR2(3)

NULL

USER_STATS

VARCHAR2(3)

NULL

DURATION

VARCHAR2(15)

NULL

SKIP_CORRUPT

VARCHAR2(8)

NULL

MONITORING

VARCHAR2(3)

NULL

Table C-26 USER_USERS

Name
Type
Value

USERNAME

VARCHAR2(30)

-

USER_ID

NUMBER

0

ACCOUNT_STATUS

VARCHAR2(32)

OPEN

LOCK_DATE

DATE

NULL

EXPIRY_DATE

DATE

NULL

DEFAULT_TABLESPACE

VARCHAR2(30)

NULL

TEMPORARY_TABLESPACE

VARCHAR2(30)

NULL

CREATED

DATE

NULL

INITIAL_RSRC_CONSUMER_GROUP

VARCHAR2(30)

NULL

EXTERNAL_NAME

VARCHAR2(4000)

NULL

Table C-27 USER_VIEWS

Name
Type
Value

VIEW_NAME

VARCHAR2(30)

-

TEXT_LENGTH

NUMBER

0

TEXT

LONG

NULL

TYPE_TEXT_LENGTH

NUMBER

0

TYPE_TEXT

VARCHAR2(4000)

NULL

OID_TEXT_LENGTH

NUMBER

0

OID_TEXT

VARCHAR2(4000)

NULL

VIEW_TYPE_OWNER

VARCHAR2(30)

NULL

VIEW_TYPE

VARCHAR2(30)

NULL

D Initialization Parameters

The Oracle database initialization parameters in the init.ora file are distinct from gateway initialization parameters. Set the gateway parameters in the initialization parameter file using an agent-specific mechanism, or set them in the Oracle data dictionary using the DBMS_HS package. The gateway initialization parameter file must be available when the gateway is started.

This appendix contains a list of the gateway initialization parameters that can be set for each gateway and their description. It also describes the initialization parameter file syntax. It includes the following sections:

Initialization Parameter File Syntax

Oracle Database Gateway for ODBC Initialization Parameters

Initialization Parameter Descriptions

Initialization Parameter File Syntax

The syntax for the initialization parameter file is as follows:

The file is a sequence of commands.

Each command should start on a separate line.

End of line is considered a command terminator (unless escaped with a backslash).

If there is a syntax error in an initialization parameter file, none of the settings take effect.

Set the parameter values as follows:

[SET][PRIVATE] parameter=value

Where:

parameter is an initialization parameter name. It is a string of characters starting with a letter and consisting of letters, digits and underscores. Initialization parameter names are case sensitive.

value is the initialization parameter value. It is case sensitive. An initialization parameter value is either:

A string of characters that does not contain any backslashes, white space or double quotation marks (")

A quoted string beginning with a double quotation mark and ending with a double quotation mark. The following can be used inside a quoted string:

backslash (\) is the escape character

\n inserts a new line

\t inserts a tab

\" inserts a double quotation mark

\\ inserts a backslash

A backslash at the end of the line continues the string on the next line. If a backslash precedes any other character then the backslash is ignored.

For example, to enable tracing for an agent, set the HS_FDS_TRACE_LEVEL initialization parameter as follows:

HS_FDS_TRACE_LEVEL=ON

SET and PRIVATE are optional keywords. You cannot use either as an initialization parameter name. Most parameters are needed only as initialization parameters, so you usually do not need to use the SET or PRIVATE keywords. If you do not specify either SET or PRIVATE, the parameter is used only as an initialization parameter for the agent.

SET specifies that, in addition to being used as an initialization parameter, the parameter value is set as an environment variable for the agent process. Use SET for parameter values that the drivers or non-Oracle system need as environment variables.

PRIVATE specifies that the initialization parameter should be private to the agent and should not be uploaded to the Oracle database. Most initialization parameters should not be private. If, however, you are storing sensitive information like a password in the initialization parameter file, then you may not want it uploaded to the server because the initialization parameters and values are not encrypted when uploaded. Making the initialization parameters private prevents the upload from happening and they do not appear in dynamic performance views. Use PRIVATE for the initialization parameters only if the parameter value includes sensitive information such as a user name or password.

SET PRIVATE specifies that the parameter value is set as an environment variable for the agent process and is also private (not transferred to the Oracle database, not appearing in dynamic performance views or graphical user interfaces).

Oracle Database Gateway for ODBC Initialization Parameters

This section lists all the initialization file parameters that can be set for the Oracle Database Gateway for ODBC. They are as follows:

HS_DB_DOMAIN

HS_DB_INTERNAL_NAME

HS_DB_NAME

HS_DESCRIBE_CACHE_HWM

HS_LANGUAGE

HS_LONG_PIECE_TRANSFER_SIZE

HS_OPEN_CURSORS

HS_RPC_FETCH_REBLOCKING

HS_RPC_FETCH_SIZE

HS_FDS_SHAREABLE_NAME

HS_TIME_ZONE

IFILE

HS_FDS_TIMESTAMP_MAPPING

HS_FDS_DATE_MAPPING

HS_FDS_CONNECT_INFO

HS_FDS_DEFAULT_OWNER

HS_FDS_TRACE_LEVEL

HS_TRANSACTION_MODEL

HS_FDS_FETCH_ROWS

HS_FDS_REMOTE_DB_CHARSET

HS_FDS_SQLLEN_INTERPRETATION

HS_FDS_REPORT_REAL_AS_DOUBLE

Initialization Parameter Description

The following sections describe all the initialization file parameters that can be set for gateways.

HS_DB_DOMAIN

Property | Description
Default value | WORLD
Range of values | 1 to 199 characters

Specifies a unique network sub-address for a non-Oracle system. The HS_DB_DOMAIN initialization parameter is similar to the DB_DOMAIN initialization parameter, described in the Oracle Database Reference. The HS_DB_DOMAIN initialization parameter is required if you use the Oracle Names server. The HS_DB_NAME and HS_DB_DOMAIN initialization parameters define the global name of the non-Oracle system.

Note:

The HS_DB_NAME and HS_DB_DOMAIN initialization parameters must combine to form a unique address in a cooperative server environment.

HS_DB_INTERNAL_NAME

Property | Description
Default value | 01010101
Range of values | 1 to 16 hexadecimal characters

Specifies a unique hexadecimal number identifying the instance to which the Heterogeneous Services agent is connected. This parameter's value is used as part of a transaction ID when global name services are activated. Specifying a nonunique number can cause problems when two-phase commit recovery actions are necessary for a transaction.

HS_DB_NAME

Property | Description
Default value | HO
Range of values | 1 to 8 characters

Specifies a unique alphanumeric name for the data store given to the non-Oracle system. This name identifies the non-Oracle system within the cooperative server environment. The HS_DB_NAME and HS_DB_DOMAIN initialization parameters define the global name of the non-Oracle system.

HS_DESCRIBE_CACHE_HWM

Property | Description
Default value | 100
Range of values | 1 to 4000

Specifies the maximum number of entries in the describe cache used by Heterogeneous Services. This limit is known as the describe cache high water mark. The cache contains descriptions of the mapped tables that Heterogeneous Services reuses so that it does not have to re-access the non-Oracle data store.

If you are accessing many mapped tables, increase the high water mark to improve performance. Increasing the high water mark improves performance at the cost of memory usage.

HS_LANGUAGE

Property | Description
Default value | System-specific
Range of values | Any valid language name (up to 255 characters)

Provides Heterogeneous Services with character set, language, and territory information of the non-Oracle data source. The value must use the following format:

language[_territory.character_set]

Note:

The globalization support initialization parameters affect error messages, the data for the SQL Service, and parameters in distributed external procedures.

Character Sets

Ideally, the character sets of the Oracle database and the non-Oracle data source are the same. In almost all cases, HS_LANGUAGE should be set exactly the same as Oracle database character set for optimal character set mapping and performance. If they are not the same, Heterogeneous Services attempts to translate the character set of the non-Oracle data source to the Oracle database character set, and back again. The translation can degrade performance. In some cases, Heterogeneous Services cannot translate a character from one character set to another.

Note:

The specified character set must be a superset of the operating system character set on the platform where the agent is installed.

As more Oracle databases and non-Oracle databases use Unicode as database character sets, it is preferable to also run the gateway in Unicode character set. To do so, you must set HS_LANGUAGE=AL32UTF8. However, when the gateway runs on Windows, the Microsoft ODBC Driver Manager interface can exchange data only in the double-byte character set, UCS2. This results in extra ratio expansion of described buffer and column sizes. Refer to HS_FDS_REMOTE_DB_CHARSET for instruction on how to adjust to correct sizes.

Language

The language component of the HS_LANGUAGE initialization parameter determines:

Day and month names of dates

AD, BC, PM, and AM symbols for date and time

Default sorting mechanism

Note that Oracle does not determine the language for error messages for the generic Heterogeneous Services messages (ORA-25000 through ORA-28000). These are controlled by the session settings in the Oracle database.

Territory

The territory clause specifies the conventions for day and week numbering, default date format, decimal character and group separator, and ISO and local currency symbols. Note that the level of globalization support between the Oracle database and the non-Oracle data source depends on how the gateway is implemented.

HS_LONG_PIECE_TRANSFER_SIZE

Property | Description
Default value | 64 KB
Range of values | Any value up to 2 GB

Sets the size of the piece of LONG data being transferred. A smaller piece size means less memory requirement, but more round-trips to fetch all the data. A larger piece size means fewer round-trips, but more of a memory requirement to store the intermediate pieces internally. Thus, the initialization parameter can be used to tune a system for the best performance, with the best trade-off between round-trips and memory requirements, and network latency or response time.

HS_OPEN_CURSORS

Property | Description
Default value | 50
Range of values | 1 to the value of OPEN_CURSORS initialization parameter of Oracle database

Defines the maximum number of cursors that can be open on one connection to a non-Oracle system instance.

The value never exceeds the number of open cursors in the Oracle database. Therefore, setting the same value as the OPEN_CURSORS initialization parameter in the Oracle database is recommended.

HS_RPC_FETCH_REBLOCKING

Property | Description
Default value | ON
Range of values | OFF or ON

Controls whether Heterogeneous Services attempts to optimize performance of data transfer between the Oracle database and the Heterogeneous Services agent connected to the non-Oracle data store.

The following values are possible:

OFF disables reblocking of fetched data so that data is immediately sent from agent to server.

ON enables reblocking, which means that data fetched from the non-Oracle system is buffered in the agent and is not sent to the Oracle database until the amount of fetched data is equal or higher than the value of HS_RPC_FETCH_SIZE initialization parameter. However, any buffered data is returned immediately when a fetch indicates that no more data exists or when the non-Oracle system reports an error.

HS_RPC_FETCH_SIZE

Property | Description
Default value | 50000
Range of values | 1 to 10000000

Tunes internal data buffering to optimize the data transfer rate between the server and the agent process.

Increasing the value can reduce the number of network round-trips needed to transfer a given amount of data, but also tends to increase data bandwidth and to reduce latency as measured between issuing a query and completion of all fetches for the query. Nevertheless, increasing the fetch size can increase latency for the initial fetch results of a query, because the first fetch results are not transmitted until additional data is available.

HS_TIME_ZONE

Property | Description
Default value for '[+|-]hh:mm' | Derived from the NLS_TERRITORY initialization parameter
Range of values for '[+|-]hh:mm' | Any valid datetime format mask

Specifies the default local time zone displacement for the current SQL session. The format mask, [+|-]hh:mm, is specified to indicate the hours and minutes before or after UTC (Coordinated Universal Time—formerly Greenwich Mean Time). For example:

HS_TIME_ZONE = [+ | -] hh:mm

HS_TRANSACTION_MODEL

Property | Description
Default Value | None
Range of Values | READ_ONLY and SINGLE_SITE

Specifies the type of transaction model that is used when the non-Oracle database is updated by a transaction.

The following values are possible:

READ_ONLY provides read access to the non-Oracle database.

SINGLE_SITE provides read and write access to the non-Oracle database. However, the gateway cannot participate in distributed updates and cannot be used with Oracle Streams to replicate data

IFILE

Property | Description
Default value | None
Range of values | Valid parameter file names

Use the IFILE initialization parameter to embed another initialization file within the current initialization file. The value should be an absolute path and should not contain environment variables. The three levels of nesting limit do not apply.

See Also:

Oracle Database Reference

HS_FDS_TIMESTAMP_MAPPING

Property | Description
Default Value | DATE
Range of Values | CHAR|DATE|TIMESTAMP
Syntax | HS_FDS_TIMESTAMP_MAPPING={CHAR|DATE|TIMESTAMP}

If set to CHAR (default), non-Oracle timestamp would be mapped to CHAR(26). If set to DATE, then non-Oracle target timestamp would be mapped to Oracle Date. If set to TIMESTAMP, non-Oracle timestamp would be mapped to Oracle timestamp.

HS_FDS_DATE_MAPPING

Property | Description
Default Value | DATE
Range of Values | DATE|CHAR
Syntax | HS_FDS_DATE_MAPPING={DATE|CHAR}

If set to CHAR, then non-oracle target date would be mapped to CHAR(10). If set to DATE, then non-Oracle target date would be mapped to Oracle Date.

HS_FDS_CONNECT_INFO

Property | Description
Default Value | None
Range of Values | Not applicable

HS_FDS_CONNECT_INFO which describes the connection to the non-Oracle system.

The default initialization parameter file already has an entry for this parameter. The syntax for HS_FDS_CONNECT_INFO for the gateway is as follows:

HS_FDS_CONNECT_INFO=dsn_value

where, dsn_value on Microsoft Windows, is the name of the system DSN defined in the Microsoft Windows ODBC Data Source Administrator and on UNIX based system, it is data source name configured in the odbc.ini file.

The entry for dsn_value is case sensitive.

HS_FDS_DEFAULT_OWNER

Property | Description
Default Value | None
Range of Values | Not applicable

The name of the table owner that is used for the non-Oracle database tables if an owner is not specified in the SQL statements.

Note:

If this parameter is not specified and the owner is not explicitly specified in the SQL statement, then the user name of the Oracle user or the user name specified when creating the database link is used.

HS_FDS_TRACE_LEVEL

Property | Description
Default Value | OFF
Range of values | OFF, ON, DEBUG

Specifies whether error tracing is turned on or off for gateway connectivity.

The following values are valid:

OFF disables the tracing of error messages.

ON enables the tracing of error messages that occur when you encounter problems. The results are written by default to a gateway log file in LOG directory where the gateway is installed.

DEBUG enables the tracing of detailed error messages that can be used for debugging.

HS_FDS_SHAREABLE_NAME

Property | Description
Default Value | None
Range of Values | Not applicable

Specifies the full path name to the ODBC driver manager.

This is a required parameter, whose format is:

HS_FDS_SHAREABLE_NAME=odbc_installation_path/lib/libodbc.sl

Where:

odbc_installation_path is the path where the ODBC driver is installed.

This parameter applies only to UNIX based platforms.

HS_FDS_FETCH_ROWS

Property | Description
Default Value | 100
Range of Values | Any integer between 1 and 1000
Syntax | HS_FDS_FETCH_ROWS=num

HS_FDS_FETCH_ROWS specifies the fetch array size. This is the number of rows to be fetched from the non-Oracle database and to return to Oracle database at one time. This parameter will be affected by the HS_RPC_FETCH_SIZE and HS_RPC_FETCH_REBLOCKING parameters.

HS_FDS_REMOTE_DB_CHARSET

Property | Description
Default Value | None
Range of values | Not applicable
Syntax | HS_FDS_REMOTE_DB_CHARSET

This parameter is valid only when HS_LANGUAGE is set to AL32UTF8 and the gateway runs on Windows. As more Oracle databases and non-Oracle databases use Unicode as database character sets, it is preferable to also run the gateway in Unicode character set. To do so, you must set HS_LANGUAGE=AL32UTF8. However, when the gateway runs on Windows, the Microsoft ODBC Driver Manager interface can exchange data only in the double-byte character set, UCS2. This results in extra ratio expansion of described buffer and column sizes. To compensate, the gateway can adjust to correct size if HS_FDS_REMOTE_DB_CHARSET is set to the corresponding non-Oracle database character set. For example, HS_FDS_REMOTE_DB_CHARSET=KO16KSC5601.

HS_FDS_SQLLEN_INTERPRETATION

Property | Description
Default Value | 64
Range of values | {64|32}
Syntax | HS_FDS_SQLLEN_INTERPRETATION= {64|32}

This parameter is only valid for 64 bit platforms. ODBC standard specifies SQLLEN (of internal ODBC construct) being 64 bit on 64 bit platforms, but some ODBC driver managers and drivers violate this convention, and implement it as 32 bit. In order for Oracle Database Gateway for ODBC to compensate their behavior, you need to specify HS_FDS_SQLLEN_INTERPRETATION=32 if you use these types of driver managers and driver.

HS_FDS_REPORT_REAL_AS_DOUBLE

Property | Description
Default Value | FALSE
Range of Values | TRUE, FALSE

Enables Oracle Database Gateway for ODBC treat SINGLE FLOAT PRECISION fields as DOUBLE FLOAT PRECISION fields.

Index

A  C  D  E  F  G  H  I  K  O  P  R  S  T  U  V  W 

A

ALTER statement, B.1

C

character sets

Heterogeneous Services, D.3.5.1

CONNECT BY clause, 2.3.2.2

CREATE statement, B.1

D

data definition language, B.1

data dictionary

contents with Oracle Database Gateway for ODBC, C.2

mapping for Oracle Database Gateway for ODBC, C.2.1

Oracle database name/SQL Server name, C.2.1

translation support for Oracle Database Gateway for ODBC, C

data dictionary views

Oracle Database Gateway for ODBC, C.2

data type

VARBINARY, 2.4.1

DELETE statement, B.1.1

describe cache high water mark

definition, D.3.4

drivers

ODBC, 1.5

DROP statement, B.1

E

Encrypted format login, 2.4.1

Error messages

error tracing, D.3.17

F

fetch array size, with HS_FDS_FETCH_ROWS, D.3.19

G

gateway

pass-through feature, 2.1

supported functions, B

supported SQL syntax, B.1

globalization support

Heterogeneous Services, D.3.5

GRANT statement, B.1

H

Heterogeneous Services

defining maximum number of open cursors, D.3.7

optimizing data transfer, D.3.8

Oracle Database Gateway for ODBC

architecture, 1.4

definition, 1.3

non-Oracle data dictionary access, C.1

ODBC connectivity requirements, 1.5

supported functions, B.2

supported SQL syntax, B.1

supported tables, C.2

setting global name, D.3.3

specifying cache high water mark, D.3.4

tuning internal data buffering, D.3.9

tuning LONG data transfer, D.3.6

HS_DB_NAME initialization parameter, D.3.3

HS_DESCRIBE_CACHE_HWM initialization parameter, D.3.4

HS_FDS_CONNECT_INFO, D.3.15

HS_FDS_DEFAULT_OWNER initialization parameter, D.3.16

HS_FDS_FETCH_ROWS parameter, D.3.19

HS_FDS_RECOVERY_PWD initialization parameter, D.3.22

HS_FDS_SHAREABLE_NAME initialization parameter, D.3.18

HS_FDS_TRACE_LEVEL initialization parameter, D.3.17

enabling agent tracing, D.1

HS_LANGUAGE initialization parameter, D.3.5

HS_LONG_PIECE_TRANSFER_SIZE initialization parameter, D.3.6

HS_OPEN_CURSORS initialization parameter, D.3.7

HS_RPC_FETCH_REBLOCKING initialization parameter, D.3.8

HS_RPC_FETCH_SIZE initialization parameter, D.3.9

HS_TIME_ZONE initialization parameter, D.3.10

I

IFILE initialization parameter, D.3.12

Initialization parameter file

customizing, D

INSERT statement, B.1.2

K

Known restrictions, 2.3

O

ODBC agents

connectivity requirements, 1.5

functions, 1.5

ODBC connectivity

data dictionary mapping, C.2.1

ODBC driver, 1.5

requirements, 1.5

specifying path to library, D.3.18

OLE DB connectivity

data dictionary mapping, C.2.1

Oracle Database Gateway for ODBC

architecture, 1.4

Oracle and non-Oracle on same machine, 1.4.2

Oracle and non-Oracle on separate machines, 1.4.1

data dictionary

translation support, C

definition, 1.3

DELETE statement, B.2

INSERT statement, B.2

non-Oracle data dictionary access, C.1

ODBC connectivity requirements, 1.5

supported functions, B.2

supported SQL syntax, B.1

UPDATE statement, B.2

P

parameters

gateway initialization file

HS_FDS_FETCH_ROWS, D.3.19

R

ROWID, 2.3.2.1, 2.3.2.3, 2.3.2.4

S

SELECT statement, B.1.3

accessing non-Oracle system, C.1

T

TRUNCATE statement, B.1

U

unsupported functions

Oracle Database Gateway for ODBC, B.2

UPDATE statement, B.1.4

V

VARBINARY data type, 2.4.1

W

WHERE CURRENT OF clause, 2.3.2.1

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