postgresql/src/backend/parser
Tom Lane 486cfb3b8c Fix parsetree representation of XMLTABLE(XMLNAMESPACES(DEFAULT ...)).
The original coding for XMLTABLE thought it could represent a default
namespace by a T_String Value node with a null string pointer.  That's
not okay, though; in particular outfuncs.c/readfuncs.c are not on board
with such a representation, meaning you'll get a null pointer crash
if you try to store a view or rule containing this construct.

To fix, change the parsetree representation so that we have a NULL
list element, instead of a bogus Value node.

This isn't really a functional limitation since default XML namespaces
aren't yet implemented in the executor; you'd just get "DEFAULT
namespace is not supported" anyway.  But crashes are not nice, so
back-patch to v10 where this syntax was added.  Ordinarily we'd consider
a parsetree representation change to be un-backpatchable; but since
existing releases would crash on the way to storing such constructs,
there can't be any existing views/rules to be incompatible with.

Per report from Andrey Lepikhov.

Discussion: https://postgr.es/m/3690074f-abd2-56a9-144a-aa5545d7a291@postgrespro.ru
2018-09-17 13:16:32 -04:00
..
.gitignore Convert cvsignore to gitignore, and add .gitignore for build targets. 2010-09-22 12:57:04 +02:00
analyze.c Fix INSERT ON CONFLICT UPDATE through a view that isn't just SELECT *. 2018-08-04 19:38:58 -04:00
check_keywords.pl Don't fall off the end of perl functions 2018-05-27 09:08:42 -04:00
gram.y Change PROCEDURE to FUNCTION in CREATE TRIGGER syntax 2018-08-22 14:45:07 +02:00
Makefile Revert MERGE patch 2018-04-12 11:22:56 +01:00
parse_agg.c Revert MERGE patch 2018-04-12 11:22:56 +01:00
parse_clause.c Fix parsetree representation of XMLTABLE(XMLNAMESPACES(DEFAULT ...)). 2018-09-17 13:16:32 -04:00
parse_coerce.c Merge catalog/pg_foo_fn.h headers back into pg_foo.h headers. 2018-04-08 14:35:29 -04:00
parse_collate.c Revert MERGE patch 2018-04-12 11:22:56 +01:00
parse_cte.c Update copyright for 2018 2018-01-02 23:30:12 -05:00
parse_enr.c Update copyright for 2018 2018-01-02 23:30:12 -05:00
parse_expr.c Revert MERGE patch 2018-04-12 11:22:56 +01:00
parse_func.c Fix misc typos, mostly in comments. 2018-07-18 16:17:42 +03:00
parse_node.c Update copyright for 2018 2018-01-02 23:30:12 -05:00
parse_oper.c Update copyright for 2018 2018-01-02 23:30:12 -05:00
parse_param.c Update copyright for 2018 2018-01-02 23:30:12 -05:00
parse_relation.c Revert MERGE patch 2018-04-12 11:22:56 +01:00
parse_target.c Indexes with INCLUDE columns and their support in B-tree 2018-04-07 23:00:39 +03:00
parse_type.c Update copyright for 2018 2018-01-02 23:30:12 -05:00
parse_utilcmd.c Fully enforce uniqueness of constraint names. 2018-09-04 13:45:35 -04:00
parser.c Update copyright for 2018 2018-01-02 23:30:12 -05:00
README Move keywords.c/kwlookup.c into src/common/. 2016-03-23 20:22:08 -04:00
scan.l Fix lexing of standard multi-character operators in edge cases. 2018-08-23 21:43:51 +01:00
scansup.c Update copyright for 2018 2018-01-02 23:30:12 -05:00

src/backend/parser/README

Parser
======

This directory does more than tokenize and parse SQL queries.  It also
creates Query structures for the various complex queries that are passed
to the optimizer and then executor.

parser.c	things start here
scan.l		break query into tokens
scansup.c	handle escapes in input strings
gram.y		parse the tokens and produce a "raw" parse tree
analyze.c	top level of parse analysis for optimizable queries
parse_agg.c	handle aggregates, like SUM(col1),  AVG(col2), ...
parse_clause.c	handle clauses like WHERE, ORDER BY, GROUP BY, ...
parse_coerce.c	handle coercing expressions to different data types
parse_collate.c	assign collation information in completed expressions
parse_cte.c	handle Common Table Expressions (WITH clauses)
parse_expr.c	handle expressions like col, col + 3, x = 3 or x = 4
parse_func.c	handle functions, table.column and column identifiers
parse_node.c	create nodes for various structures
parse_oper.c	handle operators in expressions
parse_param.c	handle Params (for the cases used in the core backend)
parse_relation.c support routines for tables and column handling
parse_target.c	handle the result list of the query
parse_type.c	support routines for data type handling
parse_utilcmd.c	parse analysis for utility commands (done at execution time)

See also src/common/keywords.c, which contains the table of standard
keywords and the keyword lookup function.  We separated that out because
various frontend code wants to use it too.