mirror of
https://github.com/postgres/postgres.git
synced 2025-05-26 18:17:33 +03:00
The NumericOnly grammar production accepted ICONST, + ICONST, - ICONST, FCONST, and - FCONST, but for some reason not + FCONST. This led to strange inconsistencies like regression=# set random_page_cost = +4; SET regression=# set random_page_cost = 4000000000; SET regression=# set random_page_cost = +4000000000; ERROR: syntax error at or near "4000000000" (because 4000000000 is too large to be an ICONST). While there's no actual functional reason to need to write a "+", if we allow it for integers it seems like we should allow it for numerics too. It's been like that forever, so back-patch to all supported branches. Discussion: https://postgr.es/m/30908.1496006184@sss.pgh.pa.us
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.