Extend column statistics analysis to include columns with GroupByColumns #141
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This commit fixes an issue where the cardinality of a column would result in zero if the column had `GroupByColumns` specified and `IsAvailableInMDX=FALSE`. This occurred because statistics for columns with IsAvailableInMDX set to FALSE are not available in the DMV $SYSTEM.DISCOVER_STORAGE_TABLES (see WHERE LEFT(TABLE_ID, 2) = 'H$' in PopulateColumnsCardinality)
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This commit fixes an issue where the cardinality of a column would result in zero if the column had
GroupByColumnsspecified andIsAvailableInMDX=false. This occurred because statistics for these columns are not available in the DMV$SYSTEM.DISCOVER_STORAGE_TABLES(seeWHERE LEFT(TABLE_ID, 2) = 'H$'in PopulateColumnsCardinality).