Row Header Compression Method - Teradata Vantage

Teradata® VantageCloud Lake

Deployment
VantageCloud
Edition
Lake
Product
Teradata Vantage
Published
January 2023
ft:locale
en-US
ft:lastEdition
2024-12-11
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This section summarizes the benefits, best uses, and restrictions of row header compression in Vantage.

Benefits of Row Header Compression

  • Only applied to columns partition that have COLUMN format
  • Reduces I/O overhead
  • Automatically applied to column partitions with COLUMN format whether you specify AUTO COMPRESS or NO AUTO COMPRESS

Best Use of Row Header Compression

  • Column partitions in COLUMN format that contain many column partition values per container

Restrictions and Limitations of Row Header Compression

  • If only a few column partition values can be placed in a container because of their width, there can be an increase in the space needed for a column-partitioned object in COLUMN format.

    ROW format may be a more appropriate choice.

  • If a combined partition contains only a few column partition values, there can be a large increase in the space needed for a column-partitioned object.

    Consider altering the row partitioning to allow for more column partition values per combined partition, reducing the number of row partitions, or removing column partitioning.

  • Overpartitioning a table loses the advantages of row header compression.