postgresql/src/backend/parser
Robert Haas 585e31fcb6 Don't generate fake "*SELECT*" or "*SELECT* %d" subquery aliases.
rte->alias should point only to a user-written alias, but in these
cases that principle was violated. Fixing this causes some regression
test output changes: wherever rte->alias previously had a value and
is now NULL, rte->eref is now set to a generated name rather than to
rte->alias; and the scheme used to generate eref names differs from
what we were doing for aliases.

The upshot is that instead of "*SELECT*" or "*SELECT* %d",
EXPLAIN will now emit "unnamed_subquery" or "unnamed_subquery_%d".
But that's a reasonable descriptor, and we were already producing
that in yet other cases, so this seems not too objectionable.

Author: Tom Lane <tgl@sss.pgh.pa.us>
Co-authored-by: Robert Haas <rhaas@postgresql.org>
Discussion: https://postgr.es/m/CA+TgmoYSYmDA2GvanzPMci084n+mVucv0bJ0HPbs6uhmMN6HMg@mail.gmail.com
2025-09-08 11:50:33 -04:00
..
.gitignore Convert cvsignore to gitignore, and add .gitignore for build targets. 2010-09-22 12:57:04 +02:00
analyze.c Don't generate fake "*SELECT*" or "*SELECT* %d" subquery aliases. 2025-09-08 11:50:33 -04:00
check_keywords.pl Update copyright for 2025 2025-01-01 11:21:55 -05:00
gram.y Add HINT for COPY TO when WHERE clause is used. 2025-09-03 08:35:55 +09:00
gramparse.h Update copyright for 2025 2025-01-01 11:21:55 -05:00
Makefile Drop warning-free support for Flex 2.5.35 2025-01-15 15:35:08 +01:00
meson.build Drop warning-free support for Flex 2.5.35 2025-01-15 15:35:08 +01:00
parse_agg.c Don't try to parallelize array_agg() on an anonymous record type. 2025-03-09 13:11:20 -04:00
parse_clause.c Relax ordering-related hardcoded btree requirements in planning 2025-04-06 14:43:51 +02:00
parse_coerce.c Require callers of coerce_to_domain() to supply base type/typmod. 2025-01-29 15:42:25 -05:00
parse_collate.c Update copyright for 2025 2025-01-01 11:21:55 -05:00
parse_cte.c Fix parse_cte.c's failure to examine sub-WITHs in DML statements. 2025-04-05 15:01:48 -04:00
parse_enr.c Update copyright for 2025 2025-01-01 11:21:55 -05:00
parse_expr.c Avoid including commands/dbcommands.h in so many places 2025-08-28 12:39:04 +02:00
parse_func.c Update copyright for 2025 2025-01-01 11:21:55 -05:00
parse_jsontable.c Update copyright for 2025 2025-01-01 11:21:55 -05:00
parse_merge.c Add OLD/NEW support to RETURNING in DML queries. 2025-01-16 14:57:35 +00:00
parse_node.c Grab the low-hanging fruit from forcing USE_FLOAT8_BYVAL to true. 2025-08-13 17:18:22 -04:00
parse_oper.c Update copyright for 2025 2025-01-01 11:21:55 -05:00
parse_param.c Update copyright for 2025 2025-01-01 11:21:55 -05:00
parse_relation.c Virtual generated columns 2025-02-07 09:46:59 +01:00
parse_target.c Avoid including commands/dbcommands.h in so many places 2025-08-28 12:39:04 +02:00
parse_type.c Update copyright for 2025 2025-01-01 11:21:55 -05:00
parse_utilcmd.c Make CREATE TABLE LIKE copy comments on NOT NULL constraints when requested. 2025-06-26 20:25:34 +09:00
parser.c Update copyright for 2025 2025-01-01 11:21:55 -05:00
README Update parser README to include parse_jsontable.c 2025-09-08 10:07:14 +09:00
scan.l Drop warning-free support for Flex 2.5.35 2025-01-15 15:35:08 +01:00
scansup.c Update copyright for 2025 2025-01-01 11:21:55 -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_enr.c	handle ephemeral named rels (trigger transition tables, ...)
parse_func.c	handle functions, table.column and column identifiers
parse_jsontable.c handle JSON_TABLE
parse_merge.c	handle MERGE
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.