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. | 
| double | coCodePercentageA Cocode parameter that differ in behavior based on compression method, in general it is a value that reflects
 aggressively likely coCoding is used. | 
| CoCoderFactory.PartitionerType | columnPartitionerThe selected method for column partitioning used in CoCoding compressed columns | 
| CostEstimatorFactory.CostType | costComputationTypeThe cost computation type for the compression | 
| SampleEstimatorFactory.EstimationType | estimationTypeThe sample type used for sampling | 
| boolean | lossyTrue if lossy compression is enabled | 
| int | maxColGroupCoCodeThe maximum number of columns CoCoded allowed | 
| int | minimumSampleSizeThe minimum size of the sample extracted. | 
| 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 | transposedTranspose input matrix, to optimize access when extracting bitmaps. | 
| String | transposeInputBoolean specifying which transpose setting is used, can be auto, true or false | 
| EnumSet<AColGroup.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 String transposeInput
public final boolean skipList
public final int seed
public final boolean lossy
public final CoCoderFactory.PartitionerType columnPartitioner
public final CostEstimatorFactory.CostType costComputationType
public final int maxColGroupCoCode
public final double coCodePercentage
public final EnumSet<AColGroup.CompressionType> validCompressions
public final int minimumSampleSize
public final SampleEstimatorFactory.EstimationType estimationType
public boolean transposed
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