17.05 - Example: Specifying Various MERGEBLOCKRATIO Settings - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Definition Language Syntax and Examples

Product
Advanced SQL Engine
Teradata Database
Release Number
17.05
Release Date
January 2021
Content Type
Programming Reference
Publication ID
B035-1144-175K
Language
English (United States)

These examples demonstrate different specifications for the MERGEBLOCKRATIO option. If the DBS Control parameter DisableMergeBlocks is set to TRUE, Vantage ignores the setting for this option globally and disables all data block merges for all tables in the system. See Teradata Vantage™ - Database Utilities , B035-1102 .

This example defines emp_table so that the system uses the value for the DBS Control parameter MergeBlockRatio as the merge block ratio when merging data blocks for the table.

     CREATE TABLE emp_table, DEFAULT MERGEBLOCKRATIO (
     emp_no INTEGER);

This example sets the value of the merge block ratio for emp_table to 25%.

     CREATE TABLE emp_table, MERGEBLOCKRATIO=25 PERCENT (
     emp_no INTEGER);

This example defines emp_table in a way that disables all data block merges.

     CREATE TABLE emp_table, NO MERGEBLOCKRATIO (
     emp_no INTEGER);