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it is sufficient to track whether a backend holds a lock or not, and store information about transaction vs. session locks only in the inside-the-backend LocalLockTable. Since there can now be but one PROCLOCK per lock per backend, LockCountMyLocks() is no longer needed, thus eliminating some O(N^2) behavior when a backend holds many locks. Also simplify the LockAcquire/LockRelease API by passing just a 'sessionLock' boolean instead of a transaction ID. The previous API was designed with the idea that per-transaction lock holding would be important for subtransactions, but now that we have subtransactions we know that this is unwanted. While at it, add an 'isTempObject' parameter to LockAcquire to indicate whether the lock is being taken on a temp table. This is not used just yet, but will be needed shortly for two-phase commit.
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. The JDBC, ODBC, C++, Python, and Tcl interfaces have been moved to the PostgreSQL Projects Web Site at http://gborg.postgresql.org for separate maintenance. A Perl DBI/DBD driver is available from CPAN. 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 ftp://ftp.postgresql.org/pub/. For more information look at our web site located at http://www.postgresql.org/.