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A pseudo table generated to show statistics cached for use by the NuoDB query optimizer. Rows in
SYSTEM.STATSCACHE represent either table or index objects in the database.
Caution: Client applications should never contain code that accesses
SYSTEM pseudo tables as they are subject to, and furthermore likely to, change from release to release.
|ID||bigint||The database ID for the table or index object.|
|VERSION||bigint||Index statistics are versioned and this field represents the version number.|
|TYPE||string||Currently this is either index or table.|
|NAME||string||The name of either the index or the table.|
|VALID||boolean||True if valid and usable by the query optimizer.|
|CARDINALITY||bigint||The cardinality of the index or table.|
|DISTINCTCOUNT||bigint||The number of distinct keys in the index, null for tables.|
|AVERAGEKEYLENGTH||double||The average length of a key in the index, null for tables.|
|HISTOGRAMCOUNT||bigint||The number of histogram buckets for the index, null for tables.|
|SPAN||string||The partitions that are spanned by the statistics. Where tables are not partitioned, or where statistics span all partitions, this column does not populate.|