postgresql/src/backend/parser
Tom Lane 02b4f5e1f2 Avoid unhelpful internal error for incorrect recursive-WITH queries.
checkWellFormedRecursion would issue "missing recursive reference"
if a WITH RECURSIVE query contained a single self-reference but
that self-reference was inside a top-level WITH, ORDER BY, LIMIT,
etc, rather than inside the second arm of the UNION as expected.
We already intended to throw more-on-point errors for such cases,
but those error checks must be done before examining the UNION arm
in order to have the desired results.  So this patch need only
move some code (and improve the comments).

Per bug #18536 from Alexander Lakhin.  Back-patch to all supported
branches.

Discussion: https://postgr.es/m/18536-0a342ec07901203e@postgresql.org
2024-07-14 13:49:46 -04:00
..
.gitignore Convert cvsignore to gitignore, and add .gitignore for build targets. 2010-09-22 12:57:04 +02:00
analyze.c Make INSERT-from-multiple-VALUES-rows handle domain target columns. 2024-03-14 14:57:16 -04:00
check_keywords.pl Update copyright for 2021 2021-01-02 13:06:25 -05:00
gram.y Rename parser token REF to REF_P to avoid a symbol conflict. 2022-10-16 15:27:04 -04:00
Makefile Split all OBJS style lines in makefiles into one-line-per-entry style. 2019-11-05 14:41:07 -08:00
parse_agg.c Compute aggregate argument types correctly in transformAggregateCall(). 2023-11-06 10:38:00 -05:00
parse_clause.c Catch stack overflow when recursing in transformFromClauseItem(). 2022-08-13 15:21:28 -04:00
parse_coerce.c Fix failure to validate the result of select_common_type(). 2022-01-29 11:41:18 -05:00
parse_collate.c Update copyright for 2021 2021-01-02 13:06:25 -05:00
parse_cte.c Avoid unhelpful internal error for incorrect recursive-WITH queries. 2024-07-14 13:49:46 -04:00
parse_enr.c Update copyright for 2021 2021-01-02 13:06:25 -05:00
parse_expr.c In transformRowExpr(), check for too many columns in the row. 2022-07-29 13:30:50 -04:00
parse_func.c Avoid O(N^2) behavior in SyncPostCheckpoint(). 2021-11-02 11:31:54 -04:00
parse_node.c In transformRowExpr(), check for too many columns in the row. 2022-07-29 13:30:50 -04:00
parse_oper.c Reconsider the handling of procedure OUT parameters. 2021-06-10 17:11:36 -04:00
parse_param.c Update copyright for 2021 2021-01-02 13:06:25 -05:00
parse_relation.c Fix type-checking of RECORD-returning functions in FROM, redux. 2024-04-15 12:56:56 -04:00
parse_target.c Make INSERT-from-multiple-VALUES-rows handle domain target columns. 2024-03-14 14:57:16 -04:00
parse_type.c Add the ability for the core grammar to have more than one parse target. 2021-01-04 11:03:22 -05:00
parse_utilcmd.c Fix handling of extended expression statistics in CREATE TABLE LIKE. 2024-05-22 17:54:17 -04:00
parser.c Re-implement pl/pgsql's expression and assignment parsing. 2021-01-04 11:52:00 -05:00
README Move keywords.c/kwlookup.c into src/common/. 2016-03-23 20:22:08 -04:00
scan.l Update copyright for 2021 2021-01-02 13:06:25 -05:00
scansup.c Update copyright for 2021 2021-01-02 13:06:25 -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.