mirror of
https://github.com/postgres/postgres.git
synced 2025-05-09 18:21:05 +03:00
c64d0cd5ce
We've been speculating for a long time that hash-based keyword lookup ought to be faster than binary search, but up to now we hadn't found a suitable tool for generating the hash function. Joerg Sonnenberger provided the inspiration, and sample code, to show us that rolling our own generator wasn't a ridiculous idea. Hence, do that. The method used here requires a lookup table of approximately 4 bytes per keyword, but that's less than what we saved in the predecessor commit afb0d0712, so it's not a big problem. The time savings is indeed significant: preliminary testing suggests that the total time for raw parsing (flex + bison phases) drops by ~20%. Patch by me, but it owes its existence to Joerg Sonnenberger; thanks also to John Naylor for review. Discussion: https://postgr.es/m/20190103163340.GA15803@britannica.bec.de
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: https://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. 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 https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.