postgresql/src/backend/parser
Tom Lane 70a7732007 Remove support for upgrading extensions from "unpackaged" state.
Andres Freund pointed out that allowing non-superusers to run
"CREATE EXTENSION ... FROM unpackaged" has security risks, since
the unpackaged-to-1.0 scripts don't try to verify that the existing
objects they're modifying are what they expect.  Just attaching such
objects to an extension doesn't seem too dangerous, but some of them
do more than that.

We could have resolved this, perhaps, by still requiring superuser
privilege to use the FROM option.  However, it's fair to ask just what
we're accomplishing by continuing to lug the unpackaged-to-1.0 scripts
forward.  None of them have received any real testing since 9.1 days,
so they may not even work anymore (even assuming that one could still
load the previous "loose" object definitions into a v13 database).
And an installation that's trying to go from pre-9.1 to v13 or later
in one jump is going to have worse compatibility problems than whether
there's a trivial way to convert their contrib modules into extension
style.

Hence, let's just drop both those scripts and the core-code support
for "CREATE EXTENSION ... FROM".

Discussion: https://postgr.es/m/20200213233015.r6rnubcvl4egdh5r@alap3.anarazel.de
2020-02-19 16:59:14 -05:00
..
.gitignore Convert cvsignore to gitignore, and add .gitignore for build targets. 2010-09-22 12:57:04 +02:00
Makefile Split all OBJS style lines in makefiles into one-line-per-entry style. 2019-11-05 14:41:07 -08:00
README Move keywords.c/kwlookup.c into src/common/. 2016-03-23 20:22:08 -04:00
analyze.c Fill in extraUpdatedCols in logical replication 2020-02-17 15:20:57 +01:00
check_keywords.pl Update copyrights for 2020 2020-01-01 12:21:45 -05:00
gram.y Remove support for upgrading extensions from "unpackaged" state. 2020-02-19 16:59:14 -05:00
parse_agg.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_clause.c Reconsider the representation of join alias Vars. 2020-01-09 11:56:59 -05:00
parse_coerce.c Make parser rely more heavily on the ParseNamespaceItem data structure. 2020-01-02 11:29:01 -05:00
parse_collate.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_cte.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_enr.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_expr.c Make parser rely more heavily on the ParseNamespaceItem data structure. 2020-01-02 11:29:01 -05:00
parse_func.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_node.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_oper.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_param.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_relation.c Reconsider the representation of join alias Vars. 2020-01-09 11:56:59 -05:00
parse_target.c Reconsider the representation of join alias Vars. 2020-01-09 11:56:59 -05:00
parse_type.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00
parse_utilcmd.c Restructure ALTER TABLE execution to fix assorted bugs. 2020-01-15 18:49:24 -05:00
parser.c Reduce size of backend scanner's tables. 2020-01-13 15:04:31 -05:00
scan.l Reduce size of backend scanner's tables. 2020-01-13 15:04:31 -05:00
scansup.c Update copyrights for 2020 2020-01-01 12:21:45 -05:00

README

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.