postgresql/src/backend/parser
Alvaro Herrera 90ad85db6a
MERGE ... DO NOTHING: require SELECT privileges
Verify that a user running MERGE with a DO NOTHING clause has
privileges to read the table, even if no columns are referenced.  Such
privileges were already required if the ON clause or any of the WHEN
conditions referenced any column at all, so there's no functional change
in practice.

This change fixes an assertion failure in the case where no column is
referenced by the command and the WHEN clauses are all DO NOTHING.

Backpatch to 15, where MERGE was introduced.

Reported-by: Alena Rybakina <a.rybakina@postgrespro.ru>
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Discussion: https://postgr.es/m/4d65a385-7efa-4436-a825-0869f89d9d92@postgrespro.ru
2024-02-21 17:18:52 +01:00
..
.gitignore Convert cvsignore to gitignore, and add .gitignore for build targets. 2010-09-22 12:57:04 +02:00
analyze.c Avoid unnecessary plancache revalidation of utility statements. 2023-08-24 12:02:40 -04:00
check_keywords.pl Update copyright for 2022 2022-01-07 19:04:57 -05:00
gram.y Fix publication syntax error message 2023-05-10 18:26:10 +02:00
Makefile Revert SQL/JSON features 2022-09-01 17:10:42 -04:00
parse_agg.c Compute aggregate argument types correctly in transformAggregateCall(). 2023-11-06 10:38:00 -05:00
parse_clause.c Update some comments that should've covered MERGE 2022-10-24 12:52:43 +02:00
parse_coerce.c Fix failure to validate the result of select_common_type(). 2022-01-29 11:41:18 -05:00
parse_collate.c Revert SQL/JSON features 2022-09-01 17:10:42 -04:00
parse_cte.c Fix inability to reference CYCLE column from inside its CTE. 2022-12-16 13:07:42 -05:00
parse_enr.c Update copyright for 2022 2022-01-07 19:04:57 -05:00
parse_expr.c Update some comments that should've covered MERGE 2022-10-24 12:52:43 +02:00
parse_func.c Add support for MERGE SQL command 2022-03-28 16:47:48 +02:00
parse_merge.c MERGE ... DO NOTHING: require SELECT privileges 2024-02-21 17:18:52 +01:00
parse_node.c In transformRowExpr(), check for too many columns in the row. 2022-07-29 13:31:11 -04:00
parse_oper.c Update copyright for 2022 2022-01-07 19:04:57 -05:00
parse_param.c Pre-beta mechanical code beautification. 2022-05-12 15:17:30 -04:00
parse_relation.c Fix more bugs caused by adding columns to the end of a view. 2023-03-07 18:21:53 -05:00
parse_target.c Track nesting depth correctly when drilling down into RECORD Vars. 2023-09-15 17:01:26 -04:00
parse_type.c Rename value node fields 2022-01-14 11:26:08 +01:00
parse_utilcmd.c Fix propagation of persistence to sequences in ALTER TABLE / ADD COLUMN 2024-02-09 08:15:27 +01:00
parser.c Revert SQL/JSON features 2022-09-01 17:10:42 -04:00
README Move keywords.c/kwlookup.c into src/common/. 2016-03-23 20:22:08 -04:00
scan.l Reject trailing junk after numeric literals 2022-02-16 10:37:31 +01:00
scansup.c Update copyright for 2022 2022-01-07 19:04:57 -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.