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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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Comparing Teradata SQL and DB2

DB2 Version 2 Release 3.0 Changes

Read Access to Common DB2 Databases Recovering Multiple Index Partitions

This is supported from a number of DB2 subsystems. The DB2 subsystems can be on the same processor or on separate processors.

and Entire Indexes. This can now be done on the same table space simultaneously. The entire recovery takes as long as the longest single RECOVER INDEX in the jobs. In Teradata RDBMS, using ARC, you can

• ARCHIVE/RESTORE index data - this way is faster than the next method.

• Not ARCHIVE index data, but BUILD the index data after the RESTORE of primary data is RESTOREd.

the DB2 COPY Utility can now produce MULTIPLE IMAGE Multiple Image C°pi.6s COPIES. A total of four image copies can be simultaneously created,

two for the local site and two for the recovery site. In case of disaster, the recovery files would be used by DB2 to recover the local system at the recovery site. DB2 COPY is similar to Teradata SQL ‘s ARCHIVE command which can make two multiple ARCHIVE images simultaneously. Hence Teradata SQL does not support multiple image copies but only two image copies.

The DB2 ARCHIVE LOG command lets a properly authorized user Archive lOg force the current active log to archive. ARCHIVE LOG is similar to

Teradata SQL‘s PERMANENT JOURNAL and the ARC utility can archive the active PERMANENT JOURNAL.

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Teradata RDBMS for UNIX SQL Reference
Comparing Teradata SQL and DB2

DB2 Version 2 Release 2.0 Changes

DB2 Version 2 Release 2.0 Changes

The following new features offered in DB2 Version 2 Release 2.0. are IntrOducUon not supported by Teradata SQL:

These capabilities are provided for a single site per commit scope Remote Update with TSO and CAF. An authorized user at Branch 1 can update,

Capabilities insert, or delete data at Branch 2 if TSO or CAF is used. However, an

update at any site, remote or local, must be committed before additional updates at a different site can be performed.

Teradata RDBMS for UNIX SQL Reference

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Comparing Teradata SQL and DB2

DB2 Version 3.0 Changes

Introduction

Multi-site Updates

More Distributed Connections

Catalog Tables

More Detailed Accounting Information

DB2 Version 3.0 Changes

The following new features offered in DB2 Version 3.0., are not supported by Teradata SQL:

A DB2 application can request and update data at multiple remote relational database management systems in a single unit of work, if those systems support IBM’s Distributed Relational Database Architecture (DRDA) with two-phase commit. Also an application that runs in an RDBNS with DRDA support can access and update data at multiple DB2s within a single unit of work; DB2 offers two ways to access remote data:

• Application-Directed Access. SQL statements can be used to connect to a remote system and run packages there. The packages can contain any kind of SQL statements.

• System-Directed Access. You can direct a query to a DB2 subsystem by using an alias or a three-part name. The query must be a data manipulation query.

A DB2 server can now have 10,000 distributed connections at any given time. 2000 of those connections can be active at the same time; the rest must be in a new inactive state.

The DB2 catalog tables have been changed.

For packages and DBRMs can now be collected.

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Teradata RDBMS for UNIX SQL Reference
Stored Procedures

Distributed Connections

Thread Management

Data Sharing

Concurrency

Performance

Comparing Teradata SQL and DB2

DB2 Version 4.0 Changes

DB2 Version 4.0 Changes

Enable the invoking of a user-written program, a stored procedure (‘macro’), at a DB2 server instead of sending statements back and forth across the network. This helps solve elapsed time costs of applications that access distributed data.

Distributed connections have increased and up to 25,000 are permitted.

Workload management for distributed threads is supported. This enables setting of dispatching priority for individual distributed threads.

• Terminated DDF threads are now cancelled avoiding wasted time and resources at a MVS/ESA server.

• Time-out period has been added for active server threads that are idle, holding locks, but doing no work.‘

With data sharing, applications can be run on many DB2 subsystems and access the same shared data. If one system goes down, the work can be rerouted to another DB2 susbsystem with no outage perceived. It is an integrated hardware/software solution.

A new type of index in Version 4, Type 2 indexes:

• do not lock index pages

• allow the use of other Version 4 enhancements such as:

• parallel query central processor processing

• improved partition independence

• row locking

• ability to read through locks

• maximum number of user locks can now be set separately by table space rather than once for the entire system

• An isolation level can be set for a single SQL statement
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