DEFAULT_ND_JOINSEL DEFAULT_ND_SEL FALLBACK_ND_JOINSEL FALLBACK_ND_SEL geo_joinsel geo_sel MIN_DIMENSION_WIDTH ND_DIMS pg_get_nd_stats pg_nd_stats_from_tuple SDFACTOR STATISTIC_KIND_2D STATISTIC_KIND_ND STATISTIC_SLOT_2D STATISTIC_SLOT_ND T_DIM X_DIM Y_DIM Z_DIM

geo_joinsel() float8 geo_joinsel ( const ND_STATS *  s1, const ND_STATS *  s2  ) Given two statistics histograms, what is the selectivity of a join driven by the && operator? Join selectivity is defined as the number of rows returned by the join operator divided by the number of rows that an unconstrained join would return (nrows1*nrows2). To get the estimate of join rows, we walk through the cells of one histogram, and multiply the cell value by the proportion of the cells in the other histogram the cell overlaps: val += val1 * ( val2 * overlap_ratio )