Columns Encoding and Compression

You can reduce Data Warehouse column storage space by applying encoding and compression techniques. Available encoding methods include:

  • Run-length encoding (sorted repeating values replaced with the value and a number of occurrences)
  • Dictionary
  • Various delta encodings

By default, the AUTO encoding is used on column values. This method applies LZO compression to CHAR/VARCHAR, BOOLEAN, BINARY/VARBINARY, and FLOAT columns.

For INTEGER, DATE/TIME/TIMESTAMP, and INTERVAL type columns, Data Warehouse uses a compression scheme based on the delta between consecutive column values.

For more detailed information on individual encoding types, see Encoding Types.