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* Change post-rewriter representation of dropped columns in joinaliasvars.Tom Lane2013-07-23
| | | | | | | | | | | | | | | | | | | | | It's possible to drop a column from an input table of a JOIN clause in a view, if that column is nowhere actually referenced in the view. But it will still be there in the JOIN clause's joinaliasvars list. We used to replace such entries with NULL Const nodes, which is handy for generation of RowExpr expansion of a whole-row reference to the view. The trouble with that is that it can't be distinguished from the situation after subquery pull-up of a constant subquery output expression below the JOIN. Instead, replace such joinaliasvars with null pointers (empty expression trees), which can't be confused with pulled-up expressions. expandRTE() still emits the old convention, though, for convenience of RowExpr generation and to reduce the risk of breaking extension code. In HEAD and 9.3, this patch also fixes a problem with some new code in ruleutils.c that was failing to cope with implicitly-casted joinaliasvars entries, as per recent report from Feike Steenbergen. That oversight was because of an inadequate description of the data structure in parsenodes.h, which I've now corrected. There were some pre-existing oversights of the same ilk elsewhere, which I believe are now all fixed.
* Make FOR UPDATE/SHARE in the primary query not propagate into WITH queries;Tom Lane2009-10-27
| | | | | | | | | | | | | | | | | | | | | | | | for example in WITH w AS (SELECT * FROM foo) SELECT * FROM w, bar ... FOR UPDATE the FOR UPDATE will now affect bar but not foo. This is more useful and consistent than the original 8.4 behavior, which tried to propagate FOR UPDATE into the WITH query but always failed due to assorted implementation restrictions. Even though we are in process of removing those restrictions, it seems correct on philosophical grounds to not let the outer query's FOR UPDATE affect the WITH query. In passing, fix isLockedRel which frequently got things wrong in nested-subquery cases: "FOR UPDATE OF foo" applies to an alias foo in the current query level, not subqueries. This has been broken for a long time, but it doesn't seem worth back-patching further than 8.4 because the actual consequences are minimal. At worst the parser would sometimes get RowShareLock on a relation when it should be AccessShareLock or vice versa. That would only make a difference if someone were using ExclusiveLock concurrently, which no standard operation does, and anyway FOR UPDATE doesn't result in visible changes so it's not clear that the someone would notice any problem. Between that and the fact that FOR UPDATE barely works with subqueries at all in existing releases, I'm not excited about worrying about it.
* Fix subquery pullup to wrap a PlaceHolderVar around the entire RowExprTom Lane2009-09-02
| | | | | | | | | | | | | | | | | | | | | | | | | | | | that's generated for a whole-row Var referencing the subquery, when the subquery is in the nullable side of an outer join. The previous coding instead put PlaceHolderVars around the elements of the RowExpr. The effect was that when the outer join made the subquery outputs go to null, the whole-row Var produced ROW(NULL,NULL,...) rather than just NULL. There are arguments afoot about whether those things ought to be semantically indistinguishable, but for the moment they are not entirely so, and the planner needs to take care that its machinations preserve the difference. Per bug #5025. Making this feasible required refactoring ResolveNew() to allow more caller control over what is substituted for a Var. I chose to make ResolveNew() a wrapper around a new general-purpose function replace_rte_variables(). I also fixed the ancient bogosity that ResolveNew might fail to set a query's hasSubLinks field after inserting a SubLink in it. Although all current callers make sure that happens anyway, we've had bugs of that sort before, and it seemed like a good time to install a proper solution. Back-patch to 8.4. The problem can be demonstrated clear back to 8.0, but the fix would be too invasive in earlier branches; not to mention that people may be depending on the subtly-incorrect behavior. The 8.4 series is new enough that fixing this probably won't cause complaints, but it might in older branches. Also, 8.4 shows the incorrect behavior in more cases than older branches do, because it is able to flatten subqueries in more cases.
* 8.4 pgindent run, with new combined Linux/FreeBSD/MinGW typedef listBruce Momjian2009-06-11
| | | | provided by Andrew.
* Revert updatable viewsPeter Eisentraut2009-01-27
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* Support column-level privileges, as required by SQL standard.Tom Lane2009-01-22
| | | | Stephen Frost, with help from KaiGai Kohei and others
* Automatic view update rulesPeter Eisentraut2009-01-22
| | | | Bernd Helmle
* Update copyright for 2009.Bruce Momjian2009-01-01
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* Implement SQL-standard WITH clauses, including WITH RECURSIVE.Tom Lane2008-10-04
| | | | | | | | | | | | | There are some unimplemented aspects: recursive queries must use UNION ALL (should allow UNION too), and we don't have SEARCH or CYCLE clauses. These might or might not get done for 8.4, but even without them it's a pretty useful feature. There are also a couple of small loose ends and definitional quibbles, which I'll send a memo about to pgsql-hackers shortly. But let's land the patch now so we can get on with other development. Yoshiyuki Asaba, with lots of help from Tatsuo Ishii and Tom Lane
* Fix more problems with rewriter failing to set Query.hasSubLinks when insertingTom Lane2008-09-24
| | | | | | | | | | a SubLink expression into a rule query. We missed cases where the original query contained a sub-SELECT in a function in FROM, a multi-row VALUES list, or a RETURNING list. Per bug #4434 from Dean Rasheed and subsequent investigation. Back-patch to 8.1; older releases don't have the issue because they didn't try to be smart about setting hasSubLinks only when needed.
* Extend the parser location infrastructure to include a location field inTom Lane2008-08-28
| | | | | | | | | | | | | most node types used in expression trees (both before and after parse analysis). This allows us to place an error cursor in many situations where we formerly could not, because the information wasn't available beyond the very first level of parse analysis. There's a fair amount of work still to be done to persuade individual ereport() calls to actually include an error location, but this gets the initdb-forcing part of the work out of the way; and the situation is already markedly better than before for complaints about unimplementable implicit casts, such as CASE and UNION constructs with incompatible alternative data types. Per my proposal of a few days ago.
* Move exprType(), exprTypmod(), expression_tree_walker(), and related routinesTom Lane2008-08-25
| | | | | | into nodes/nodeFuncs, so as to reduce wanton cross-subsystem #includes inside the backend. There's probably more that should be done along this line, but this is a start anyway.
* Update copyrights in source tree to 2008.Bruce Momjian2008-01-01
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* Small comment spacing improvement.Bruce Momjian2007-11-16
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* Fix pgindent to properly handle 'else' and single-line comments on theBruce Momjian2007-11-15
| | | | | same line; previous fix was only partial. Re-run pgindent on files that need it.
* Make eval_const_expressions() preserve typmod when simplifying something likeTom Lane2007-09-06
| | | | | | | | | | | null::char(3) to a simple Const node. (It already worked for non-null values, but not when we skipped evaluation of a strict coercion function.) This prevents loss of typmod knowledge in situations such as exhibited in bug #3598. Unfortunately there seems no good way to fix that bug in 8.1 and 8.2, because they simply don't carry a typmod for a plain Const node. In passing I made all the other callers of makeNullConst supply "real" typmod values too, though I think it probably doesn't matter anywhere else.
* Changes pg_trigger and extend pg_rewrite in order to allow triggers andJan Wieck2007-03-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | rules to be defined with different, per session controllable, behaviors for replication purposes. This will allow replication systems like Slony-I and, as has been stated on pgsql-hackers, other products to control the firing mechanism of triggers and rewrite rules without modifying the system catalog directly. The firing mechanisms are controlled by a new superuser-only GUC variable, session_replication_role, together with a change to pg_trigger.tgenabled and a new column pg_rewrite.ev_enabled. Both columns are a single char data type now (tgenabled was a bool before). The possible values in these attributes are: 'O' - Trigger/Rule fires when session_replication_role is "origin" (default) or "local". This is the default behavior. 'D' - Trigger/Rule is disabled and fires never 'A' - Trigger/Rule fires always regardless of the setting of session_replication_role 'R' - Trigger/Rule fires when session_replication_role is "replica" The GUC variable can only be changed as long as the system does not have any cached query plans. This will prevent changing the session role and accidentally executing stored procedures or functions that have plans cached that expand to the wrong query set due to differences in the rule firing semantics. The SQL syntax for changing a triggers/rules firing semantics is ALTER TABLE <tabname> <when> TRIGGER|RULE <name>; <when> ::= ENABLE | ENABLE ALWAYS | ENABLE REPLICA | DISABLE psql's \d command as well as pg_dump are extended in a backward compatible fashion. Jan
* Fix up the remaining places where the expression node structure would loseTom Lane2007-03-17
| | | | | | | | | | | | | | available information about the typmod of an expression; namely, Const, ArrayRef, ArrayExpr, and EXPR and ARRAY SubLinks. In the ArrayExpr and SubLink cases it wasn't really the data structure's fault, but exprTypmod() being lazy. This seems like a good idea in view of the expected increase in typmod usage from Teodor's work to allow user-defined types to have typmods. In particular this responds to the concerns we had about eliminating the special-purpose hack that exprTypmod() used to have for BPCHAR Consts. We can now tell whether or not such a Const has been cast to a specific length, and report or display properly if so. initdb forced due to changes in stored rules.
* Fix markQueryForLocking() to work correctly in the presence of nested views.Tom Lane2007-03-01
| | | | | It has been wrong for this case since it was first written for 7.1 :-( Per report from Pavel Hanák.
* Wording cleanup for error messages. Also change can't -> cannot.Bruce Momjian2007-02-01
| | | | | | | | | | | | | | Standard English uses "may", "can", and "might" in different ways: may - permission, "You may borrow my rake." can - ability, "I can lift that log." might - possibility, "It might rain today." Unfortunately, in conversational English, their use is often mixed, as in, "You may use this variable to do X", when in fact, "can" is a better choice. Similarly, "It may crash" is better stated, "It might crash".
* Update CVS HEAD for 2007 copyright. Back branches are typically notBruce Momjian2007-01-05
| | | | back-stamped for this.
* Message style improvementsPeter Eisentraut2006-10-06
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* pgindent run for 8.2.Bruce Momjian2006-10-04
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* Apply a simple solution to the problem of making INSERT/UPDATE/DELETETom Lane2006-09-02
| | | | | | | | | | | | | | | RETURNING play nice with views/rules. To wit, have the rule rewriter rewrite any RETURNING clause found in a rule to produce what the rule's triggering query asked for in its RETURNING clause, in particular drop the RETURNING clause if no RETURNING in the triggering query. This leaves the responsibility for knowing how to produce the view's output columns on the rule author, without requiring any fundamental changes in rule semantics such as adding new rule event types would do. The initial implementation constrains things to ensure that there is exactly one, unconditionally invoked RETURNING clause among the rules for an event --- later we might be able to relax that, but for a post feature freeze fix it seems better to minimize how much invention we do. Per gripe from Jaime Casanova.
* Add support for multi-row VALUES clauses as part of INSERT statementsJoe Conway2006-08-02
| | | | | | (e.g. "INSERT ... VALUES (...), (...), ...") and elsewhere as allowed by the spec. (e.g. similar to a FROM clause subselect). initdb required. Joe Conway and Tom Lane.
* Remove 576 references of include files that were not needed.Bruce Momjian2006-07-14
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* Improve the representation of FOR UPDATE/FOR SHARE so that we canTom Lane2006-04-30
| | | | | | support both FOR UPDATE and FOR SHARE in one command, as well as both NOWAIT and normal WAIT behavior. The more general code is actually simpler and cleaner.
* Fix a bunch of problems with domains by making them use special input functionsTom Lane2006-04-05
| | | | | | | | | | | that apply the necessary domain constraint checks immediately. This fixes cases where domain constraints went unchecked for statement parameters, PL function local variables and results, etc. We can also eliminate existing special cases for domains in places that had gotten it right, eg COPY. Also, allow domains over domains (base of a domain is another domain type). This almost worked before, but was disallowed because the original patch hadn't gotten it quite right.
* Update copyright for 2006. Update scripts.Bruce Momjian2006-03-05
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* Fix problems with rewriter failing to set Query.hasSubLinks when insertingTom Lane2005-11-23
| | | | | | | a SubLink expression into a rule query. Pre-8.1 we essentially did this unconditionally; 8.1 tries to do it only when needed, but was missing a couple of cases. Per report from Kyle Bateman. Add some regression test cases covering this area.
* Re-run pgindent, fixing a problem where comment lines after a blankBruce Momjian2005-11-22
| | | | | | | | | comment line where output as too long, and update typedefs for /lib directory. Also fix case where identifiers were used as variable names in the backend, but as typedefs in ecpg (favor the backend for indenting). Backpatch to 8.1.X.
* Standard pgindent run for 8.1.Bruce Momjian2005-10-15
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* Add NOWAIT option to SELECT FOR UPDATE/SHARE.Tom Lane2005-08-01
| | | | | Original patch by Hans-Juergen Schoenig, revisions by Karel Zak and Tom Lane.
* Make use of new list primitives list_append_unique and list_concat_uniqueTom Lane2005-07-28
| | | | where applicable.
* Replace pg_shadow and pg_group by new role-capable catalogs pg_authidTom Lane2005-06-28
| | | | | | | | and pg_auth_members. There are still many loose ends to finish in this patch (no documentation, no regression tests, no pg_dump support for instance). But I'm going to commit it now anyway so that Alvaro can make some progress on shared dependencies. The catalog changes should be pretty much done.
* Change expandRTE() and ResolveNew() back to taking just the singleTom Lane2005-06-04
| | | | | | RTE of interest, rather than the whole rangetable list. This makes the API more understandable and avoids duplicate RTE lookups. This patch reverts no-longer-needed portions of my patch of 2004-08-19.
* Revise handling of dropped columns in JOIN alias lists to avoid aTom Lane2005-06-03
| | | | | | | | | | | | | | | | | | | | | performance problem pointed out by phil@vodafone: to wit, we were spending O(N^2) time to check dropped-ness in an N-deep join tree, even in the case where the tree was freshly constructed and couldn't possibly mention any dropped columns. Instead of recursing in get_rte_attribute_is_dropped(), change the data structure definition: the joinaliasvars list of a JOIN RTE must have a NULL Const instead of a Var at any position that references a now-dropped column. This costs nothing during normal parse-rewrite-plan path, and instead we have a linear-time update to make when loading a stored rule that might contain now-dropped columns. While at it, move the responsibility for acquring locks on relations referenced by rules into this separate function (which I therefore chose to call AcquireRewriteLocks). This saves effort --- namely, duplicated lock grabs in parser and rewriter --- in the normal path at a cost of one extra non-locked heap_open() in the stored-rule path; seems a good tradeoff. A fringe benefit is that it is now *much* clearer that we acquire lock on relations referenced in rules before we make any rewriter decisions based on their properties. (I don't know of any bug of that ilk, but it wasn't exactly clear before.)
* Avoid unnecessary call of rangeTableEntry_used() for the result relationTom Lane2005-05-29
| | | | of a query.
* Implement sharable row-level locks, and use them for foreign key referencesTom Lane2005-04-28
| | | | | | | | | | | | | | | to eliminate unnecessary deadlocks. This commit adds SELECT ... FOR SHARE paralleling SELECT ... FOR UPDATE. The implementation uses a new SLRU data structure (managed much like pg_subtrans) to represent multiple- transaction-ID sets. When more than one transaction is holding a shared lock on a particular row, we create a MultiXactId representing that set of transactions and store its ID in the row's XMAX. This scheme allows an effectively unlimited number of row locks, just as we did before, while not costing any extra overhead except when a shared lock actually has to be shared. Still TODO: use the regular lock manager to control the grant order when multiple backends are waiting for a row lock. Alvaro Herrera and Tom Lane.
* Merge Resdom nodes into TargetEntry nodes to simplify code and save aTom Lane2005-04-06
| | | | | | | | | few palloc's. I also chose to eliminate the restype and restypmod fields entirely, since they are redundant with information stored in the node's contained expression; re-examining the expression at need seems simpler and more reliable than trying to keep restype/restypmod up to date. initdb forced due to change in contents of stored rules.
* Rewrite rewriteTargetList() to avoid O(N^2) behavior on wide target lists.Tom Lane2005-03-26
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* Make the behavior of HAVING without GROUP BY conform to the SQL spec.Tom Lane2005-03-10
| | | | | | | | | Formerly, if such a clause contained no aggregate functions we mistakenly treated it as equivalent to WHERE. Per spec it must cause the query to be treated as a grouped query of a single group, the same as appearance of aggregate functions would do. Also, the HAVING filter must execute after aggregate function computation even if it itself contains no aggregate functions.
* Tag appropriate files for rc3PostgreSQL Daemon2004-12-31
| | | | | | | | Also performed an initial run through of upgrading our Copyright date to extend to 2005 ... first run here was very simple ... change everything where: grep 1996-2004 && the word 'Copyright' ... scanned through the generated list with 'less' first, and after, to make sure that I only picked up the right entries ...
* Fix one more place where we were expecting lcons() to be nondestructiveTom Lane2004-11-20
| | | | | | | to the original List; per report from Sebastian BÎck. I think this is the last such bug --- I examined every lcons() call in the backend and the rest seem OK --- but it's nervous-making that we're still finding 'em so many months after the List rewrite went in.
* When implementing a coercion to a domain type with a combinedTom Lane2004-11-06
| | | | | | type-and-length coercion function, make sure that the coercion function is told the correct typmod. Fixes Kris Jurka's example of a domain over bit(N).
* Pgindent run for 8.0.Bruce Momjian2004-08-29
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* Update copyright to 2004.Bruce Momjian2004-08-29
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* Repair some issues with column aliases and RowExpr construction in theTom Lane2004-08-19
| | | | | | | | | | | | presence of dropped columns. Document the already-presumed fact that eref aliases in relation RTEs are supposed to have entries for dropped columns; cause the user alias structs to have such entries too, so that there's always a one-to-one mapping to the underlying physical attnums. Adjust expandRTE() and related code to handle the case where a column that is part of a JOIN has been dropped. Generalize expandRTE()'s API so that it can be used in a couple of places that formerly rolled their own implementation of the same logic. Fix ruleutils.c to suppress display of aliases for columns that were dropped since the rule was made.
* Don't try to rewrite NEW references in a utility statement in a rule.Tom Lane2004-08-07
| | | | | | | | There won't be any, and in fact there won't even be an RTE for NEW, which was leading to a core dump in CVS tip. 7.4 and earlier manage not to crash when applying ResolveNew in this scenario, but I think it was just good fortune that they didn't. Per report from Bernd Helmle.
* Represent type-specific length coercion functions as pg_cast entries,Tom Lane2004-06-16
| | | | | | | | | | | | | | | | | eliminating the former hard-wired convention about their names. Allow pg_cast entries to represent both type coercion and length coercion in a single step --- this is represented by a function that takes an extra typmod argument, just like a length coercion function. This nicely merges the type and length coercion mechanisms into something at least a little cleaner than we had before. Make use of the single- coercion-step behavior to fix integer-to-bit coercion so that coercing to bit(n) yields the rightmost n bits of the integer instead of the leftmost n bits. This should fix recurrent complaints about the odd behavior of this coercion. Clean up the documentation of the bit string functions, and try to put it where people might actually find it. Also, get rid of the unreliable heuristics in ruleutils.c about whether to display nested coercion steps; instead require parse_coerce.c to label them properly in the first place.