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This involves two main changes from the previous behavior. First, when we set a bit in the visibility map, emit a new WAL record of type XLOG_HEAP2_VISIBLE. Replay sets the page-level PD_ALL_VISIBLE bit and the visibility map bit. Second, when inserting, updating, or deleting a tuple, we can no longer get away with clearing the visibility map bit after releasing the lock on the corresponding heap page, because an intervening crash might leave the visibility map bit set and the page-level bit clear. Making this work requires a bit of interface refactoring. In passing, a few minor but related cleanups: change the test in visibilitymap_set and visibilitymap_clear to throw an error if the wrong page (or no page) is pinned, rather than silently doing nothing; this case should never occur. Also, remove duplicate definitions of InvalidXLogRecPtr. Patch by me, review by Noah Misch.
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/.