Excerpts from Florian Pflug's message of mar sep 27 08:28:00 -0300 2011: > On Sep27, 2011, at 10:44 , andurkar wrote: > > Currently I am working on Postgresql... I need to study the gram.y and > > scan.l parser files...since I want to do some qery modification. Can anyone > > please help me to understand the files. What should I do ? Is there any > > documentation available ? > > scan.l defines the lexer, i.e. the algorithm that splits a string (containing > an SQL statement) into a stream of tokens. A token is usually a single word > (i.e., doesn't contain spaces but is delimited by spaces), but can also be > a whole single or double-quoted string for example. The lexer is basically > defined in terms of regular expressions which describe the different token > types.
Seemed a good answer so I added it to the developer's faq http://wiki.postgresql.org/wiki/Developer_FAQ#I_need_to_do_some_changes_to_query_parsing._Can_you_succintly_explain_the_parser_files.3F Feel free to edit. -- Álvaro Herrera <alvhe...@commandprompt.com> The PostgreSQL Company - Command Prompt, Inc. PostgreSQL Replication, Consulting, Custom Development, 24x7 support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers