mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-12-21 08:29:39 +08:00
7e0cce0265
Do read/write permissions checks at most once per large object descriptor, not once per lo_read or lo_write call as before. The repeated tests were quite useless in the read case since the snapshot-based tests were guaranteed to produce the same answer every time. In the write case, the extra tests could in principle detect revocation of write privileges after a series of writes has started --- but there's a race condition there anyway, since we'd check privileges before performing and certainly before committing the write. So there's no real advantage to checking every single time, and we might as well redefine it as "only check the first time". On the same reasoning, remove the LargeObjectExists checks in inv_write and inv_truncate. We already checked existence when the descriptor was opened, and checking again doesn't provide any real increment of safety that would justify the cost. |
||
|---|---|---|
| config | ||
| contrib | ||
| doc | ||
| src | ||
| .gitignore | ||
| aclocal.m4 | ||
| configure | ||
| configure.in | ||
| COPYRIGHT | ||
| GNUmakefile.in | ||
| Makefile | ||
| README | ||
| README.git | ||
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/.