Example: Modifying MERGEBLOCKRATIO - Teradata Vantage - Analytics Database

SQL Data Definition Language Syntax and Examples

Deployment
VantageCloud
VantageCore
Edition
VMware
Enterprise
IntelliFlex
Product
Analytics Database
Teradata Vantage
Release Number
17.20
Published
June 2022
ft:locale
en-US
ft:lastEdition
2025-11-06
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jco1628111346878.ditamap
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qkf1628213546010.ditaval
dita:id
mdr1472255012272
lifecycle
latest
Product Category
Teradata Vantageā„¢

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;