BRIN minmax-multi indexes
Adds BRIN opclasses similar to the existing minmax, except that instead of summarizing the page range into a single [min,max] range, the summary consists of multiple ranges and/or points, allowing gaps. This allows more efficient handling of data with poor correlation to physical location within the table and/or outlier values, for which the regular minmax opclassed tend to work poorly. It's possible to specify the number of values kept for each page range, either as a single point or an interval boundary. CREATE TABLE t (a int); CREATE INDEX ON t USING brin (a int4_minmax_multi_ops(values_per_range=16)); When building the summary, the values are combined into intervals with the goal to minimize the "covering" (sum of interval lengths), using a support procedure computing distance between two values. Bump catversion, due to various catalog changes. Author: Tomas Vondra <tomas.vondra@postgresql.org> Reviewed-by: Alvaro Herrera <alvherre@alvh.no-ip.org> Reviewed-by: Alexander Korotkov <aekorotkov@gmail.com> Reviewed-by: Sokolov Yura <y.sokolov@postgrespro.ru> Reviewed-by: John Naylor <john.naylor@enterprisedb.com> Discussion: https://postgr.es/m/c1138ead-7668-f0e1-0638-c3be3237e812@2ndquadrant.com Discussion: https://postgr.es/m/5d78b774-7e9c-c94e-12cf-fef51cc89b1a%402ndquadrant.com
Showing
This diff is collapsed.
This diff is collapsed.
This diff is collapsed.
This diff is collapsed.
This diff is collapsed.
This diff is collapsed.
This diff is collapsed.
This diff is collapsed.
This diff is collapsed.
This diff is collapsed.
Please register or sign in to comment