public class CompressionSettings extends Object
| Modifier and Type | Field and Description | 
|---|---|
| boolean | allowSharedDictionaryShare DDC Dictionaries between ColGroups. | 
| static int | BITMAP_BLOCK_SZSize of the blocks used in a blocked bitmap representation. | 
| PlanningCoCoder.PartitionerType | columnPartitionerThe selected method for column partitioning used in CoCoding compressed columns | 
| boolean | investigateEstimateBoolean specifying if the compression strategy should be investigated and monitored. | 
| boolean | lossyTrue if lossy compression is enabled | 
| int | maxStaticColGroupCoCodeThe maximum number of columns CoCoded if the Static CoCoding strategy is selected | 
| double | samplingRatioThe sampling ratio used when choosing ColGroups. | 
| int | seedIf the seed is -1 then the system used system millisecond time and class hash for seeding. | 
| boolean | skipListBoolean specifying if the OLE and RLE should construct skip to enable skipping large amounts of rows. | 
| boolean | sortValuesByLengthSorting of values by physical length helps by 10-20%, especially for serial, while slight performance decrease
 for parallel incl multi-threaded, hence not applied for distributed operations (also because compression time +
 garbage collection increases) | 
| boolean | transposeInputTranspose input matrix, to optimize performance, this reallocate the matrix to a more cache conscious allocation
 for iteration in columns. | 
| EnumSet<ColGroup.CompressionType> | validCompressionsValid Compressions List, containing the ColGroup CompressionTypes that are allowed to be used for the compression
 Default is to always allow for Uncompromisable ColGroup. | 
public static final int BITMAP_BLOCK_SZ
public final boolean sortValuesByLength
public final double samplingRatio
public final boolean allowSharedDictionary
public final boolean transposeInput
public final boolean skipList
public final int seed
public final boolean investigateEstimate
public final boolean lossy
public final PlanningCoCoder.PartitionerType columnPartitioner
public final int maxStaticColGroupCoCode
public final EnumSet<ColGroup.CompressionType> validCompressions
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