DBIx::MyParsePP

DBIx::MyParsePP(3)   User Contributed Perl Documentation   DBIx::MyParsePP(3)



NAME
       DBIx::MyParsePP - Pure-perl SQL parser based on MySQL grammar and
       lexer

SYNOPSIS
	 use DBIx::MyParsePP;
	 use Data::Dumper;

	 my $parser = DBIx::MyParsePP->new();

	 my $query = $parser->parse("SELECT 1");

	 print Dumper $query;
	 print $query->toString();

DESCRIPTION
       "DBIx::MyParsePP" is a pure-perl SQL parser that implements the MySQL
       grammar and lexer.  The grammar was automatically converted from the
       original "sql_yacc.yy" file by removing all the C code. The lexer
       comes from "sql_lex.cc", completely translated in Perl almost verba-
       tim.

       The grammar is converted into Perl form using Parse::Yapp.

CONSTRUCTOR
       "charset", "version", "sql_mode", "client_capabilities" and "stmt_pre-
       pare_mode" can be passed as arguments to the constructor. Please "use
       DBIx::MyParsePP::Lexer" to bring in the required constants and see
       DBIx::MyParsePP::Lexer for information.

METHODS
       "DBIx::MyParsePP" provides "parse()" which takes the string to be
       parsed.	The result is a DBIx::MyParsePP::Query object which contains
       the result from the parsing.

       Queries can be reconstructed back into SQL by calling the "toString()"
       method.

SPECIAL CONSIDERATIONS
       The file containing the grammar "lib/DBIx/MyParsePP/Parser.pm" is
       about 5 megabytes in size and takes a while to load. Compex statements
       take a while to parse, e.g. the first Twins query from the MySQL man-
       ual can only be parsed at a speed of few queries per second per 1GHz
       of CPU. If you require a full-speed parsing solution, please take a
       look at DBIx::MyParse, which requires a GCC compiler and produces more
       concise parse trees.

       The parse trees produced by "DBIx::MyParsePP" contain one leaf for
       every grammar rule that has been matched, even rules that serve no
       useful purpose. Therefore, parsing event simple statements such as
       "SELECT 1" produce trees dozens of levels deep. Please exercise cau-
       tion when walking those trees recursively. The DBIx::MyParsePP::Rule
       module contains the "extract()" and "shrink()" methods which are use-
       ful for dealing with the inherent complexity of the MySQL grammar.

USING GRAMMARS FROM OTHER MYSQL VERSIONS
       The package by default parses strings using the grammar from MySQL
       version 5.0.45. If you wish to use the grammar from a different ver-
       sion, you can use the "bin/myconvpp.pl" script to prepare the grammar:

	       $ perl bin/myconvpp.pl --

SEE ALSO
       For Yacc grammars, please see the Bison manual at:

	       http://www.gnu.org/software/bison

       For generating Yacc parsers in Perl, please see:

	       http://search.cpan.org/~fdesar

       For a full-speed C++-based parser that generates nicer parse trees,
       please see DBIx::MyParse

AUTHOR
       Philip Stoev, <philip@stoev.org>

COPYRIGHT AND LICENSE
       Copyright (C) 2007 by Philip Stoev

       This library is free software; you can redistribute it and/or modify
       it under the terms of the GNU General Public Licence as specified in
       the README and LICENCE files.

       Please note that this module contains code copyright by MySQL AB
       released under the GNU General Public Licence, and not the GNU Lesser
       General Public Licence.	Using this code for commercial purposes may
       require purchasing a licence from MySQL AB.

       The Parse::Yapp module and its related modules and shell scripts are
       copyright (c) 1998-2001 Francois Desarmenien, France. All rights
       reserved.



perl v5.8.8			  2007-08-17		   DBIx::MyParsePP(3)