Oracle Transparent Gateway for Ingres II Administrator's Guide
Release 8.1.6

Part Number A82871-01

Contents

Index

Go to previous page. Go to next page.

A
Supported SQL Syntax and Functions

This appendix contains the following sections:.

Supported SQL Statements

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, use the pass-through feature of the gateway if you need to use DDL statements against the Ingres II database.

See Also:

"Using the Pass-Through Feature" and Oracle8i SQL Reference for a detailed descriptions of keywords, parameters, and options. 

DELETE

The DELETE statement is fully supported. However, only Oracle functions supported by Ingres II can be used.

See Also:

"Functions Supported by Ingres II" for a list of supported functions. 

INSERT

The INSERT statement is fully supported. However, only Oracle functions supported by Ingres II can be used.

See Also:

"Functions Supported by Ingres II" for a list of supported functions. 

SELECT

The SELECT statement is fully supported, with the following exceptions:

UPDATE

The UPDATE statement is fully supported. However, only Oracle functions supported by Ingres II can be used. Column values can be set only to expressions; they cannot be set with subqueries.

See Also:

"Functions Supported by Ingres II" for a list of supported functions. 

Oracle Functions

All functions are evaluated by the Ingres II database after the gateway has converted them to Ingres II equivalents.

Functions Not Supported by Ingres II

Oracle SQL functions that have no equivalent function in OpenIngres are not supported in DELETE, INSERT, or UPDATE statements but are evaluated by the Oracle database server if the statement is a SELECT statement. That is, the Oracle database server performs post-processing of SELECT statements sent to the gateway.

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

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


Note:

The Oracle database server treats SELECT statements that contain a FOR UPDATE clause as UPDATE statements; it cannot perform post-processing of those statements. 


Functions Supported by Ingres II

The gateway translates the following Oracle database server functions in SQL statements to their equivalent Ingres II functions:

Arithmetic Operators

Oracle  OpenIngres 

Comparison Operators

Oracle  OpenIngres 

>= 

>= 

<= 

<= 

<>,!=,^= 

<>, != 

BETWEEN X AND Y 

BETWEEN X AND Y 

IS NULL 

IS NULL 

IS NOT NULL 

IS NOT NULL 

NOT BETWEEN X AND Y 

NOT BETWEEN X AND Y 

Group Functions

Oracle  OpenIngres 

AVG 

AVG 

COUNT 

COUNT 

MAX 

MAX 

MIN 

MIN 

SUM 

SUM 

String Functions

Oracle  OpenIngres 

|| 

LENGTH 

LENGTH 

LOWER 

LOWERCASE 

SUBSTR (with 2 arguments - the arguments cannot be negative numbers) 

shift('string', from) 

SUBSTR (with 3 arguments - the arguments cannot be negative numbers) 

left(shift('string', from), for) 

UPPER 

UPPERCASE 

Pattern Matches

Oracle  OpenIngres 

LIKE 'a%' 

LIKE "a%", MATCHES "a*" 

LIKE 'a_' 

LIKE "a_", MATCHES "a?" 

LIKE 'a\%' ESCAPE '\' 

LIKE "a\%" ESCAPE "\" 

NOT LIKE 

NOT LIKE 

Other Functions

Oracle  OpenIngres 

ABS 

ABS 

COS 

COS 

EXP 

EXP 

LN 

LOG 

MOD 

MOD 

NVL 

IFNULL 

POSITION 

LOCATION 

RTRIM 

TRIM 

SIN 

SIN 

SQRT 

SQRT 


Go to previous page. Go to next page.
Oracle logo.
Copyright © 2000 Oracle Corporation.

All Rights Reserved.

Contents

Index