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Kotva
parametre_pre_pgsql parametre_pre_pgsql

 Configuration parameters of depository data compressionfor compression for PostgreSQL platform:

• Kotva
  trezorcompress trezorcompress

  TrezorCompress - parameter activates depository data compression. Data is compressed when the depository is disconnected.
  The parameter can be changed online, by the SET_OPTION TrezorCompress command.
  
  

• Kotva
  trezorcompresskeep trezorcompresskeep

  TrezorCompressKeep - parameter is used to test depository depository data compression. If set to 1, the original data table (DATA) will not be deleted but will be retained. However, the data will be read from tables with compressed data (CDATA, DATA0). The TREZOR DECOMPRESS command can be used to return very quickly to the original structure of the vault, as it is not necessary to perform decompression, but simply delete the tables with compressed data.
  The parameter can be changed online, by the SET_OPTION TrezorCompressKeep command.

To delete the compressed data and to keep the original uncompressed data, follow these steps:

- Use the TREZOR_COMPRESS_KEEP SET_OPTION TrezorCompressKeep OFF command to set the value of the TrezorCompressKeep parameter to 0.

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- Use the TREZOR DECOMPRESS command to decompress the depository data (decompression will take place quickly, as only the depository will be marked as decompressed. Thanks to the value of the parameter TrezorCompressKeep = 1, the tables CDATA and DATA0 with compressed data will not be deleted).

- Use the TREZOR_COMPRESS_KEEP OFF command SET_OPTION TrezorCompressKeep OFF command to set the value of the TrezorCompressKeep parameter to 0.

- Use the TREZOR COMPRESS command to compress the depository data (compression will take place quickly, as the existing data in the compressed data tables will be used).

• Kotva
  trezorcompressreorg trezorcompressreorg

  TrezorCompressReorg - reorganization of the depository data before compression. This parameter has a default value of 1 - in practice, it turns out that it is more efficient and faster to reorganize the data first (by an SQL command CLUSTER DATA) and then compress them. A value of 0 disables reorganization of the depository data before compression. Disabling reorganization before compression is not recommended.
  The parameter can be changed online, by the SET_OPTION TrezorCompressReorg  command.
  

• Kotva
  trezorcompresscmt trezorcompresscmt

  TrezorCompressCmt  -the parameter specifies the number of archive objects after the compression of which a COMMIT will be executed. The default value is 10. In applications with intensively archived objects (many values of one archive object in the depository ), this parameter can be reduced down to 1. Conversely, in applications with many archive objects that change infrequently, it is possible to increase the value of this parameter.
  The parameter can be changed online, by the SET_OPTION TrezorCompressCmt command.
  
  

• Kotva
  trezorcompressorder trezorcompressorder

  TrezorCompressOrder - the parameter refers to reading from depositories with compressed data. This parameter indicates whether time sorting is required when reading data from a compressed depository. Since the data is sorted during compression, it is possible to leave the parameter at 0 by default, which speeds up reading from the compressed vault (ORDER BY clause is omitted)
  The parameter can be changed online, by the SET_OPTION TrezorCompressOrder command.