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which comparison operators to use for plan nodes involving tuple comparison (Agg, Group, Unique, SetOp). Formerly the executor looked up the default equality operator for the datatype, which was really pretty shaky, since it's possible that the data being fed to the node is sorted according to some nondefault operator class that could have an incompatible idea of equality. The planner knows what it has sorted by and therefore can provide the right equality operator to use. Also, this change moves a couple of catalog lookups out of the executor and into the planner, which should help startup time for pre-planned queries by some small amount. Modify the planner to remove some other cavalier assumptions about always being able to use the default operators. Also add "nulls first/last" info to the Plan node for a mergejoin --- neither the executor nor the planner can cope yet, but at least the API is in place.
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 including some of the more common listed below: C++ - http://thaiopensource.org/development/libpqxx/ JDBC - http://jdbc.postgresql.org ODBC - http://odbc.postgresql.org Perl - http://search.cpan.org/~dbdpg/ PHP - http://www.php.net Python - http://www.initd.org/ Ruby - http://ruby.scripting.ca/postgres/ Other language binding are available from a variety of contributing parties. PostgreSQL also has a great number of procedural languages available, a short but not complete list is below: PL/pgSQL - included in PostgreSQL source distribution PL/Perl - included in PostgreSQL source distribution PL/PHP - http://projects.commandprompt.com/projects/public/plphp PL/Python - included in PostgreSQL source distribution PL/Java - http://gborg.postgresql.org/project/pljava/projdisplay.php PL/Tcl - included in PostgreSQL source distribution 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/.