mirror of
https://github.com/postgres/postgres.git
synced 2026-02-23 18:04:41 -05:00
a0b012a1ab
grammar allows ALTER TABLE/INDEX/SEQUENCE/VIEW interchangeably for all subforms of those commands, and then we sort out what's really legal at execution time. This allows the ALTER SEQUENCE/VIEW reference pages to fully document all the ALTER forms available for sequences and views respectively, and eliminates a longstanding cause of confusion for users. The net effect is that the following forms are allowed that weren't before: ALTER SEQUENCE OWNER TO ALTER VIEW ALTER COLUMN SET/DROP DEFAULT ALTER VIEW OWNER TO ALTER VIEW SET SCHEMA (There's no actual functionality gain here, but formerly you had to say ALTER TABLE instead.) Interestingly, the grammar tables actually get smaller, probably because there are fewer special cases to keep track of. I did not disallow using ALTER TABLE for these operations. Perhaps we should, but there's a backwards-compatibility issue if we do; in fact it would break existing pg_dump scripts. I did however tighten up ALTER SEQUENCE and ALTER VIEW to reject non-sequences and non-views in the new cases as well as a couple of cases where they didn't before. The patch doesn't change pg_dump to use the new syntaxes, either. |
||
|---|---|---|
| .. | ||
| .cvsignore | ||
| analyze.c | ||
| gram.y | ||
| keywords.c | ||
| Makefile | ||
| parse_agg.c | ||
| parse_clause.c | ||
| parse_coerce.c | ||
| parse_expr.c | ||
| parse_func.c | ||
| parse_node.c | ||
| parse_oper.c | ||
| parse_relation.c | ||
| parse_target.c | ||
| parse_type.c | ||
| parse_utilcmd.c | ||
| parser.c | ||
| README | ||
| scan.l | ||
| scansup.c | ||
$PostgreSQL: pgsql/src/backend/parser/README,v 1.10 2008/04/09 01:00:46 momjian Exp $ 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 keywords.c turn keywords into specific tokens gram.y parse the tokens and fill query-type-specific structures analyze.c top level of parse analysis for optimizable queries parse_clause.c handle clauses like WHERE, ORDER BY, GROUP BY, ... parse_coerce.c handle coercing expressions to different data types parse_expr.c handle expressions like col, col + 3, x = 3 or x = 4 parse_oper.c handle operators in expressions parse_agg.c handle aggregates, like SUM(col1), AVG(col2), ... parse_func.c handle functions, table.column and column identifiers parse_node.c create nodes for various structures parse_target.c handle the result list of the query parse_relation.c support routines for tables and column handling parse_type.c support routines for data type handling parse_utilcmd.c parse analysis for utility commands (done at execution time)