19 Commits (31edbadf4af45dd4eecebcb732702ec6d7ae1819)

Author	SHA1	Message	Date
Tom Lane	31edbadf4a	Downgrade implicit casts to text to be assignment-only, except for the ones ... from the other string-category types; this eliminates a lot of surprising interpretations that the parser could formerly make when there was no directly applicable operator. Create a general mechanism that supports casts to and from the standard string types (text,varchar,bpchar) for *every* datatype, by invoking the datatype's I/O functions. These new casts are assignment-only in the to-string direction, explicit-only in the other, and therefore should create no surprising behavior. Remove a bunch of thereby-obsoleted datatype-specific casting functions. The "general mechanism" is a new expression node type CoerceViaIO that can actually convert between *any* two datatypes if their external text representations are compatible. This is more general than needed for the immediate feature, but might be useful in plpgsql or other places in future. This commit does nothing about the issue that applying the concatenation operator || to non-text types will now fail, often with strange error messages due to misinterpreting the operator as array concatenation. Since it often (not always) worked before, we should either make it succeed or at least give a more user-friendly error; but details are still under debate. Peter Eisentraut and Tom Lane	19 years ago
Tom Lane	7bddca3450	Fix up foreign-key mechanism so that there is a sound semantic basis for the ... equality checks it applies, instead of a random dependence on whatever operators might be named "=". The equality operators will now be selected from the opfamily of the unique index that the FK constraint depends on to enforce uniqueness of the referenced columns; therefore they are certain to be consistent with that index's notion of equality. Among other things this should fix the problem noted awhile back that pg_dump may fail for foreign-key constraints on user-defined types when the required operators aren't in the search path. This also means that the former warning condition about "foreign key constraint will require costly sequential scans" is gone: if the comparison condition isn't indexable then we'll reject the constraint entirely. All per past discussions. Along the way, make the RI triggers look into pg_constraint for their information, instead of using pg_trigger.tgargs; and get rid of the always error-prone fixed-size string buffers in ri_triggers.c in favor of building up the RI queries in StringInfo buffers. initdb forced due to columns added to pg_constraint and pg_trigger.	19 years ago
Tom Lane	13ea825b6d	Spell "explicitly" correctly, per Simon.	20 years ago
Neil Conway	adfeef55cb	When enqueueing after-row triggers for updates of a table with a foreign ... key, compare the new and old row versions. If the foreign key column has not changed, we needn't enqueue the trigger, since the update cannot violate the foreign key. This optimization was previously applied in the RI trigger function, but it is more efficient to avoid firing the trigger altogether. Per recent discussion on pgsql-hackers. Also add a regression test for some unintuitive foreign key behavior, and refactor some code that deals with the OIDs of the various RI trigger functions.	21 years ago
Tom Lane	fcbc438727	Label CVS tip as 8.0devel instead of 7.5devel. Adjust various comments ... and documentation to reference 8.0 instead of 7.5.	22 years ago
Tom Lane	077db40fa1	ALTER TABLE rewrite. New cool stuff: ... * ALTER ... ADD COLUMN with defaults and NOT NULL constraints works per SQL spec. A default is implemented by rewriting the table with the new value stored in each row. * ALTER COLUMN TYPE. You can change a column's datatype to anything you want, so long as you can specify how to convert the old value. Rewrites the table. (Possible future improvement: optimize no-op conversions such as varchar(N) to varchar(N+1).) * Multiple ALTER actions in a single ALTER TABLE command. You can perform any number of column additions, type changes, and constraint additions with only one pass over the table contents. Basic documentation provided in ALTER TABLE ref page, but some more docs work is needed. Original patch from Rod Taylor, additional work from Tom Lane.	22 years ago
Tom Lane	b88fa3b196	Generate a WARNING when the column types in a foreign key constraint are ... incompatible enough to prevent indexscanning the referenced table. Also, improve the error message that pops out when we can't implement the FK at all for lack of a usable equality operator. Fabien Coelho, with some review by Tom Lane.	22 years ago
Tom Lane	42ce74bf17	COMMENT ON casts, conversions, languages, operator classes, and ... large objects. Dump all these in pg_dump; also add code to pg_dump user-defined conversions. Make psql's large object code rely on the backend for inserting/deleting LOB comments, instead of trying to hack pg_description directly. Documentation and regression tests added. Christopher Kings-Lynne, code reviewed by Tom	22 years ago
Jan Wieck	774f57038a	Moved the recently added test for foreign key disabled by rewrite ... rule into the rule.sql since it affects the latter if run in paralell. Jan	23 years ago
Jan Wieck	cc4baf4da3	Fix for possible referential integrity violation when a qualified ON INSERT ... rule split the query into one INSERT and one UPDATE where the UPDATE then hit's the just created row without modifying the key fields again. In this special case, the new key slipped in totally unchecked. Jan	23 years ago
Bruce Momjian	1e5a16cc9c	The deferred trigger queue pushing to disk patch pointed out ... that the regression tests for foreign keys didn't seem to test a deferred constraint that was not satisified by a later statement and was not made immediate by set constraints, so here's a simple added test with a single invalid insert and a commit. Stephan Szabo	23 years ago
Bruce Momjian	b813554dbd	Improve documentation of trigger firing queue handling, cleanup. ... Neil Conway	24 years ago
Tom Lane	7c6df91dda	Second phase of committing Rod Taylor's pg_depend/pg_constraint patch. ... pg_relcheck is gone; CHECK, UNIQUE, PRIMARY KEY, and FOREIGN KEY constraints all have real live entries in pg_constraint. pg_depend exists, and RESTRICT/CASCADE options work on most kinds of DROP; however, pg_depend is not yet very well populated with dependencies. (Most of the ones that are present at this point just replace formerly hardwired associations, such as the implicit drop of a relation's pg_type entry when the relation is dropped.) Need to add more logic to create dependency entries, improve pg_dump to dump constraints in place of indexes and triggers, and add some regression tests.	24 years ago
Tom Lane	53cedcac22	Retire xlateSqlType/xlateSqlFunc; all type name translations are now ... handled as special productions. This is needed to keep us honest about user-schema type names that happen to coincide with system type names. Per pghackers discussion 24-Apr. To avoid bloating the keyword list too much, I removed the translations for datetime, timespan, and lztext, all of which were slated for destruction several versions back anyway.	24 years ago
Tom Lane	902a6a0a4b	Restructure representation of aggregate functions so that they have pg_proc ... entries, per pghackers discussion. This fixes aggregates to live in namespaces, and also simplifies/speeds up lookup in parse_func.c. Also, add a 'proimplicit' flag to pg_proc that controls whether a type coercion function may be invoked implicitly, or only explicitly. The current settings of these flags are more permissive than I would like, but we will need to debate and refine the behavior; for now, I avoided breaking regression tests as much as I could.	24 years ago
Bruce Momjian	8678929c22	This patch should catch cases where the types ... in referencing and referenced columns of an fk constraint aren't comparable using '=' at constraint definition time rather than insert/update time. Stephan Szabo	25 years ago
Tom Lane	981a7d32d1	From Stephan Szabo: ... I believe this should fix the issue that Philip Warner noticed about the check for unique constraints meeting the referenced keys of a foreign key constraint allowing the specification of a subset of a foreign key instead of rejecting it. I also added tests for a base case of this to the foreign key and alter table tests and patches for expected output.	25 years ago
Bruce Momjian	d4f626507c	This is mostly the same as an earlier patch I ... didn't hear anything about, but which would have broken with the function manager changes anyway. Well, this patch checks that a unique constraint of some form (unique or pk) is on the referenced columns of an FK constraint and that the columns in the referencing table exist at creation time. The former is to move closer to SQL compatibility and the latter is in answer to a bug report. I also added a basic check of this functionality to the alter table and foreign key regression tests. Stephan Szabo sszabo@bigpanda.com	26 years ago
Bruce Momjian	5cdfaea899	Add missing files like foreign key regression tests and config.h.win32.	26 years ago