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* Add new files.Bruce Momjian2003-03-27
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* This patch implements holdable cursors, following the proposalBruce Momjian2003-03-27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (materialization into a tuple store) discussed on pgsql-hackers earlier. I've updated the documentation and the regression tests. Notes on the implementation: - I needed to change the tuple store API slightly -- it assumes that it won't be used to hold data across transaction boundaries, so the temp files that it uses for on-disk storage are automatically reclaimed at end-of-transaction. I added a flag to tuplestore_begin_heap() to control this behavior. Is changing the tuple store API in this fashion OK? - in order to store executor results in a tuple store, I added a new CommandDest. This works well for the most part, with one exception: the current DestFunction API doesn't provide enough information to allow the Executor to store results into an arbitrary tuple store (where the particular tuple store to use is chosen by the call site of ExecutorRun). To workaround this, I've temporarily hacked up a solution that works, but is not ideal: since the receiveTuple DestFunction is passed the portal name, we can use that to lookup the Portal data structure for the cursor and then use that to get at the tuple store the Portal is using. This unnecessarily ties the Portal code with the tupleReceiver code, but it works... The proper fix for this is probably to change the DestFunction API -- Tom suggested passing the full QueryDesc to the receiveTuple function. In that case, callers of ExecutorRun could "subclass" QueryDesc to add any additional fields that their particular CommandDest needed to get access to. This approach would work, but I'd like to think about it for a little bit longer before deciding which route to go. In the mean time, the code works fine, so I don't think a fix is urgent. - (semi-related) I added a NO SCROLL keyword to DECLARE CURSOR, and adjusted the behavior of SCROLL in accordance with the discussion on -hackers. - (unrelated) Cleaned up some SGML markup in sql.sgml, copy.sgml Neil Conway
* GetTupleForTrigger must use outer transaction's command counter for timeTom Lane2003-03-27
| | | | qual checking, not GetCurrentCommandId. Per test case from Steve Wolfe.
* Add start time to pg_stat_activityBruce Momjian2003-03-20
| | | | Neil Conway
* Implement SQL92-compatible FIRST, LAST, ABSOLUTE n, RELATIVE n optionsTom Lane2003-03-11
| | | | for FETCH and MOVE.
* Restructure parsetree representation of DECLARE CURSOR: now it's aTom Lane2003-03-10
| | | | | | | | | | | | utility statement (DeclareCursorStmt) with a SELECT query dangling from it, rather than a SELECT query with a few unusual fields in it. Add code to determine whether a planned query can safely be run backwards. If DECLARE CURSOR specifies SCROLL, ensure that the plan can be run backwards by adding a Materialize plan node if it can't. Without SCROLL, you get an error if you try to fetch backwards from a cursor that can't handle it. (There is still some discussion about what the exact behavior should be, but this is necessary infrastructure in any case.) Along the way, make EXPLAIN DECLARE CURSOR work.
* Revise tuplestore and nodeMaterial so that we don't have to read theTom Lane2003-03-09
| | | | | | | | | | entire contents of the subplan into the tuplestore before we can return any tuples. Instead, the tuplestore holds what we've already read, and we fetch additional rows from the subplan as needed. Random access to the previously-read rows works with the tuplestore, and doesn't affect the state of the partially-read subplan. This is a step towards fixing the problems with cursors over complex queries --- we don't want to stick in Materialize nodes if they'll prevent quick startup for a cursor.
* COALESCE() and NULLIF() are now first-class expressions, not macrosTom Lane2003-02-16
| | | | | that turn into CASE expressions. They evaluate their arguments at most once. Patch by Kris Jurka, review and (very light) editorializing by me.
* Fix SPI result logic for case where there are multiple statements of theTom Lane2003-02-14
| | | | same type in a rule. Per bug report from Pavel Hanak.
* Create a distinction between Lists of integers and Lists of OIDs, to getTom Lane2003-02-09
| | | | | | rid of the assumption that sizeof(Oid)==sizeof(int). This is one small step towards someday supporting 8-byte OIDs. For the moment, it doesn't do much except get rid of a lot of unsightly casts.
* Make further use of new bitmapset code: executor's chgParam, extParam,Tom Lane2003-02-09
| | | | | | | | locParam lists can be converted to bitmapsets to speed updating. Also, replace 'locParam' with 'allParam', which contains all the paramIDs relevant to the node (i.e., the union of extParam and locParam); this saves a step during SetChangedParamList() without costing anything elsewhere.
* Detect duplicate aggregate calls and evaluate only one copy. ThisTom Lane2003-02-04
| | | | | speeds up some useful real-world cases like SELECT x, COUNT(*) FROM t GROUP BY x HAVING COUNT(*) > 100.
* Determine the set of constraints applied to a domain at executorTom Lane2003-02-03
| | | | | | startup, not in the parser; this allows ALTER DOMAIN to work correctly with domain constraint operations stored in rules. Rod Taylor; code review by Tom Lane.
* Tweak planner and executor to avoid doing ExecProject() in table scanTom Lane2003-02-03
| | | | | | | | nodes where it's not really necessary. In many cases where the scan node is not the topmost plan node (eg, joins, aggregation), it's possible to just return the table tuple directly instead of generating an intermediate projection tuple. In preliminary testing, this reduced the CPU time needed for 'SELECT COUNT(*) FROM foo' by about 10%.
* Fix nodeUnique to behave correctly when reversing direction after reachingTom Lane2003-02-02
| | | | | either end of subplan results. This prevents misbehavior of cursors on SELECT DISTINCT ... queries. Per bug report 1-Feb-02.
* SPI_exec shouldn't return SPI_OK_SELECT if it hasn't actually returnedTom Lane2003-01-29
| | | | | a tuple table. Fixes core dump in pltcl (and probably other PLs) when executing a query rewritten by a rule. Per bug report from Wolfgang Walter.
* Upgrade cost estimation for joins, per discussion with Bradley Baetz.Tom Lane2003-01-27
| | | | | | | Try to model the effect of rescanning input tuples in mergejoins; account for JOIN_IN short-circuiting where appropriate. Also, recognize that mergejoin and hashjoin clauses may now be more than single operator calls, so we have to charge appropriate execution costs.
* Change CREATE TABLE AS / SELECT INTO to create the new table with OIDs,Tom Lane2003-01-23
| | | | | for backwards compatibility with pre-7.3 behavior. Per discussion on pgsql-general and pgsql-hackers.
* Fix coredump problem in plpgsql's RETURN NEXT. When a SELECT INTOTom Lane2003-01-21
| | | | | | | | that's selecting into a RECORD variable returns zero rows, make it assign an all-nulls row to the RECORD; this is consistent with what happens when the SELECT INTO target is not a RECORD. In support of this, tweak the SPI code so that a valid tuple descriptor is returned even when a SPI select returns no rows.
* IN clauses appearing at top level of WHERE can now be handled as joins.Tom Lane2003-01-20
| | | | | | | | | | There are two implementation techniques: the executor understands a new JOIN_IN jointype, which emits at most one matching row per left-hand row, or the result of the IN's sub-select can be fed through a DISTINCT filter and then joined as an ordinary relation. Along the way, some minor code cleanup in the optimizer; notably, break out most of the jointree-rearrangement preprocessing in planner.c and put it in a new file prep/prepjointree.c.
* Fix wrong/misleading comments, be more consistent about where to callTom Lane2003-01-12
| | | | ExecAssignResultTypeFromTL().
* Replace RelidGetNamespaceId() by get_rel_namespace().Peter Eisentraut2003-01-12
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* First cut at implementing IN (and NOT IN) via hashtables. There isTom Lane2003-01-12
| | | | more to be done yet, but this is a good start.
* Create a new file executor/execGrouping.c to centralize utility routinesTom Lane2003-01-10
| | | | shared by nodeGroup, nodeAgg, and soon nodeSubplan.
* Read-only transactions, as defined in SQL.Peter Eisentraut2003-01-10
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* Further tweaking of parsetree & plantree representation of SubLinks.Tom Lane2003-01-10
| | | | | | | Simplify SubLink by storing just a List of operator OIDs, instead of a list of incomplete OpExprs --- that was a bizarre and bulky choice, with no redeeming social value since we have to build new OpExprs anyway when forming the plan tree.
* Adjust parser so that 'x NOT IN (subselect)' is converted toTom Lane2003-01-09
| | | | | | | | | | | 'NOT (x IN (subselect))', that is 'NOT (x = ANY (subselect))', rather than 'x <> ALL (subselect)' as we formerly did. This opens the door to optimizing NOT IN the same way as IN, whereas there's no hope of optimizing the expression using <>. Also, convert 'x <> ALL (subselect)' to the NOT(IN) style, so that the optimization will be available when processing rules dumped by older Postgres versions. initdb forced due to small change in SubLink node representation.
* Guard against stopping when numberTuples=0 and counter wraps around.Tom Lane2003-01-08
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* Adjust Tcl-related code to compile cleanly with Tcl 8.4 (add const modifiers asTom Lane2002-12-30
| | | | needed). Some desultory const-ification of SPI interface to support this.
* Better solution to integer overflow problem in hash batch-numberTom Lane2002-12-30
| | | | | | | computation: reduce the bucket number mod nbatch. This changes the association between original bucket numbers and batches, but that doesn't matter. Minor other cleanups in hashjoin code to help centralize decisions.
* Adjust hash table sizing algorithm to avoid integer overflow inTom Lane2002-12-29
| | | | | ExecHashJoinGetBatch(). Fixes core dump on large hash joins, as in example from Rae Stiening.
* Don't try to free executor state of an InitPlan early --- this breaksTom Lane2002-12-26
| | | | EXPLAIN ANALYZE. (Premature optimization is the root of all evil?)
* Update EvalPlanQual() to work with new executor memory management method.Tom Lane2002-12-18
| | | | It doesn't leak memory anymore ...
* Prevent core dump when ExecMarkPos is called before any tuples have beenTom Lane2002-12-18
| | | | | retrieved. This cannot happen in ordinary execution, but it can happen under EvalPlanQual().
* Skip unnecessary plan-copying now that plan trees are read-only in theTom Lane2002-12-17
| | | | executor.
* Tweak default memory context allocation policy so that a context is notTom Lane2002-12-15
| | | | | | | | | given any malloc block until something is first allocated in it; but thereafter, MemoryContextReset won't release that first malloc block. This preserves the quick-reset property of the original policy, without forcing 8K to be allocated to every context whether any of it is ever used or not. Also, remove some more no-longer-needed explicit freeing during ExecEndPlan.
* Revise executor APIs so that all per-query state structure is built inTom Lane2002-12-15
| | | | | | a per-query memory context created by CreateExecutorState --- and destroyed by FreeExecutorState. This provides a final solution to the longstanding problem of memory leaked by various ExecEndNode calls.
* Clean up plantree representation of SubPlan-s --- SubLink does not appearTom Lane2002-12-14
| | | | | | | | in the planned representation of a subplan at all any more, only SubPlan. This means subselect.c doesn't scribble on its input anymore, which seems like a good thing; and there are no longer three different possible interpretations of a SubLink. Simplify node naming and improve comments in primnodes.h. No change to stored rules, though.
* Phase 3 of read-only-plans project: ExecInitExpr now builds expressionTom Lane2002-12-13
| | | | | | | execution state trees, and ExecEvalExpr takes an expression state tree not an expression plan tree. The plan tree is now read-only as far as the executor is concerned. Next step is to begin actually exploiting this property.
* Preliminary code review for domain CHECK constraints patch: add documentation,Tom Lane2002-12-12
| | | | | | | | make VALUE a non-reserved word again, use less invasive method of passing ConstraintTestValue into transformExpr, fix problems with nested constraint testing, do correct thing with NULL result from a constraint expression, remove memory leak. Domain checks still need much more work if we are going to allow ALTER DOMAIN, however.
* Phase 2 of read-only-plans project: restructure expression-tree nodesTom Lane2002-12-12
| | | | | | | | | so that all executable expression nodes inherit from a common supertype Expr. This is somewhat of an exercise in code purity rather than any real functional advance, but getting rid of the extra Oper or Func node formerly used in each operator or function call should provide at least a little space and speed improvement. initdb forced by changes in stored-rules representation.
* Re-addd Rod's ALTER DOMAIN patch.Bruce Momjian2002-12-06
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* Back out ALTER DOMAIN patch until missing file appears.Bruce Momjian2002-12-06
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* ALTER DOMAIN .. SET / DROP NOT NULLBruce Momjian2002-12-06
| | | | | | | | | | ALTER DOMAIN .. SET / DROP DEFAULT ALTER DOMAIN .. ADD / DROP CONSTRAINT New files: - doc/src/sgml/ref/alter_domain.sgml Rod Taylor
* Phase 1 of read-only-plans project: cause executor state nodes to pointTom Lane2002-12-05
| | | | | | | | | | to plan nodes, not vice-versa. All executor state nodes now inherit from struct PlanState. Copying of plan trees has been simplified by not storing a list of SubPlans in Plan nodes (eliminating duplicate links). The executor still needs such a list, but it can build it during ExecutorStart since it has to scan the plan tree anyway. No initdb forced since no stored-on-disk structures changed, but you will need a full recompile because of node-numbering changes.
* More cleanup of userid to be AclId rather than Oid.Bruce Momjian2002-12-05
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* Fix ExecMakeTableFunctionResult() to work with generic expressions asTom Lane2002-12-01
| | | | | | well as function calls. This is needed for cases where the planner has constant-folded or inlined the original function call. Possibly we should back-patch this change into 7.3 branch as well.
* Code review for IS DISTINCT FROM patch. Fix incorrect constant-foldingTom Lane2002-11-30
| | | | | | logic, dissuade planner from thinking that 'x IS DISTINCT FROM 42' may be optimized into 'x = 42' (!!), cause dependency on = operator to be recorded correctly, minor other improvements.
* Be more realistic about plans involving Materialize nodes: take theirTom Lane2002-11-30
| | | | cost into account while planning.
* Upgrade planner and executor to allow multiple hash keys for a hash join,Tom Lane2002-11-30
| | | | | | instead of only one. This should speed up planning (only one hash path to consider for a given pair of relations) as well as allow more effective hashing, when there are multiple hashable joinclauses.
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