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In the initial cut at the "parameterized paths" feature, I'd simplified create_index_paths() to the point where it would only generate a single parameterized bitmap path per relation. Experimentation with an example supplied by Josh Berkus convinces me that that's not good enough: we really need to consider a bitmap path for each possible outer relation. Otherwise we have regressions relative to pre-9.2 versions, in which the planner picks a plain indexscan where it should have used a bitmap scan in queries involving three or more tables. Indeed, after fixing this, several queries in the regression tests show improved plans as a result of using bitmap not plain indexscans.
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: http://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. Changes between all PostgreSQL releases are recorded in the file HISTORY. 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 http://www.postgresql.org/download/. For more information look at our web site located at http://www.postgresql.org/.