de0dc1a847
When estimating the number of pre-sorted groups in cost_incremental_sort we must not pass Vars with varno 0 to estimate_num_groups, which would cause failues in find_base_rel. This may happen when sorting output of set operations, thanks to generate_append_tlist. Unlike recurse_set_operations we can't easily access the original target list, so if we find any Vars with varno 0, we fall back to the default estimate DEFAULT_NUM_DISTINCT. Reported-by: Justin Pryzby Discussion: https://postgr.es/m/20200411214639.GK2228%40telsasoft.com
PostgreSQL Database Management System ===================================== This directory contains the source code distribution of the PostgreSQL database management system. PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings. PostgreSQL has many language interfaces, many of which are listed here: https://www.postgresql.org/download/ See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.