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Teradata RDBMS forUNIX SQL Reference - NCR

NCR Teradata RDBMS forUNIX SQL Reference - NCR, 1997. - 913 p.
Download (direct link): teradataforunix1997.pdf
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Because EDITPROC is most often used to reduce the amount of data which is actually stored on disk, the COMPRESS capability of the Teradata RDBMS (which DB2 does not support) could be construed as providing similar functionality to EDITPROC.

Teradata RDBMS and DB2 each have a set of privileges, mostly associated with administrative and utility functions, that have no direct analog in the other system.

Teradata RDBMS and DB2 handle table locking slightly differently.

In DB2, a LOCK TABLE statement locks tablespace.

In Teradata RDBMS, a LOCK statement locks the table, unless the LOCK ROW statement is specified.

Teradata RDBMS for UNIX SQL Reference
Comparing Teradata SQL and DB2

DB2 and Teradata SQL Differences

Teradata RDBMS allows a LOCK statement as a stand-alone statement or as a modifier to any other statement and permits LOCKING as a synonym for LOCK.

Teradata RDBMS for UNIX SQL Reference

C-7
Comparing Teradata SQL and DB2

DB2 Version 2 Release 3.0 Changes

DB2 Version 2 Release 3.0 Changes

Introduction

The following are new features offered in DB2 Version 2 Release 3.0., which Teradata SQL does not support:

Remote Unit of Work

This allows a DB2 application to request and update data at a remote relational database management system that supports IBM’s Distributed Relational Database Architecture (DRDA). Also, applications operating on non-DB2 systems can access data at a DB2 server. This feature is not supported in Teradata SQL.

SQL Standards

In Release 3.0, DB2 can:

• Specify a UNIQUE constraint on a set of columns when creating a table

Note: Teradata SQL supports this feature.

Use GRANT OPTION when granting the UPDATE privilege on a set of columns

Determine, when precompiling, whether SQL statements are compliant with SAA or ISO/ANSI standards

Note: In Teradata SQL, Version 2 Release 2.0 compliance checking when precompiling will be supported for Entry Level ANSI 92.

Use double byte character strings as ordinary identifiers. Use N as well as G as a prefix for graphic string constants. Use N as well as G in VS COBOL II PICTURE clauses for DBCS data declarations

Note: Teradata SQL supports this feature.

Log Capture Exit

A new log capture exit enables the use of an exit routine to make DB2 log data available for recovery purposes in real time. The log capture exit routine receives log data when DB2 writes data to the active log. Teradata SQL does not support this feature.

Capture Changed Data

Using new syntax for CREATE TABLE and ALTER TABLE, DB2 can now capture changed data to the log in an expanded format usable by recovery programs, such as Log Apply Feature of the RRDF (Remote Recovery Data Facility) Release 2 program. Teradata SQL does not support this feature.

C-8

Teradata RDBMS for UNIX SQL Reference
Comparing Teradata SQL and DB2

DB2 Version 2 Release 3.0 Changes

English and German

Users can now enter questions in either English or German sentences using SAA LanguageAccess which is a new query product that users can access through QMF.

WITH HOLD Option

A new WITH HOLD option on the DECLARE CURSOR SQL statement allows programmers to avoid reopening the cursor after issuing COMMIT, thus avoiding the additional processing required to reposition the cursor. Teradata SQL does not support WITH HOLD.

BIND Enhancements

These allow users to bind a package at a remote or local site, provided that site is running a relational database management system that conforms to DRDA. The package tells DB2 how to get to data, like a ‘plan‘ does, but packages reside where the data is located, and plans reside where the application is running. Teradata SQL does not support BIND Enhancements.

Maintaining Large Applications

Whether or not they use remote or distributed unit of work, should be easier because of packages. If an application program uses packages, future changes do not require rebinding the whole application. The program that has been changed can be rebound by itself, saving time. It is also easier to maintain multiple versions of the same program. Teradata SQL does not support the ‘maintenance of large applications’.

Number of Columns

The maximum number of columns in a DB2 table has increased from 300 to 750.

Index Key Columns

The number of index key columns you can specify in a SQL CREATE INDEX statement increases from 16 to 64.

Precision of Decimal Numbers

LIKE Predicate

The maximum precision of decimal numbers has been extended from 15 to 31 digits.

The user can specify an ESCAPE character, which allows the use of percent and underscore characters as search arguments. This feature is supported in Teradata RDBMS V2R2.0.

Remote Secondary Authorization IDs

When DB2 receives a query from a remote location, a user-written exit routine can associate a list of secondary IDs with the primary ID, in the same way it does for queries that originate locally.

Teradata RDBMS for UNIX SQL Reference
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