17.10 - Example: Modifying MERGEBLOCKRATIO - Advanced SQL Engine - Teradata Database

Teradata Vantage™ - SQL Data Definition Language Syntax and Examples

Product
Advanced SQL Engine
Teradata Database
Release Number
17.10
Release Date
July 2021
Content Type
Programming Reference
Publication ID
B035-1144-171K
Language
English (United States)

These examples demonstrate how to use ALTER TABLE requests to modify the merge block ratio setting for an individual table.

The first example changes the default merge block ratio for emp_table so that the system retrieves the current value for the DBS Control parameter MergeBlockRatio and applies this value when merging smaller data blocks into a larger data block.

     ALTER TABLE emp_table, DEFAULT MERGEBLOCKRATIO;

The next example modifies the current setting of the merge block ratio for emp_table to 25%.

     ALTER TABLE emp_table, MERGEBLOCKRATIO = 25 PERCENT;

The final example disables all data block merging for emp_table.

     ALTER TABLE emp_table, NO MERGEBLOCKRATIO;