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2005-01-28Improve planner's estimation of the space needed for HashAgg plans:Tom Lane
look at the actual aggregate transition datatypes and the actual overhead needed by nodeAgg.c, instead of using pessimistic round numbers. Per a discussion with Michael Tiemann.
2004-12-31Tag appropriate files for rc3PostgreSQL Daemon
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 ...
2004-12-11Instead of supposing (wrongly, in the general case) that the rowtypeTom Lane
of an inheritance child table is binary-compatible with the rowtype of its parent, invent an expression node type that does the conversion correctly. Fixes the new bug exhibited by Kris Shannon as well as a lot of old bugs that would only show up when using multiple inheritance or after altering the parent table.
2004-12-02Make some adjustments to reduce platform dependencies in plan selection.Tom Lane
In particular, there was a mathematical tie between the two possible nestloop-with-materialized-inner-scan plans for a join (ie, we computed the same cost with either input on the inside), resulting in a roundoff error driven choice, if the relations were both small enough to fit in sort_mem. Add a small cost factor to ensure we prefer materializing the smaller input. This changes several regression test plans, but with any luck we will now have more stability across platforms.
2004-12-01Change planner to use the current true disk file size as its estimate ofTom Lane
a relation's number of blocks, rather than the possibly-obsolete value in pg_class.relpages. Scale the value in pg_class.reltuples correspondingly to arrive at a hopefully more accurate number of rows. When pg_class contains 0/0, estimate a tuple width from the column datatypes and divide that into current file size to estimate number of rows. This improved methodology allows us to jettison the ancient hacks that put bogus default values into pg_class when a table is first created. Also, per a suggestion from Simon, make VACUUM (but not VACUUM FULL or ANALYZE) adjust the value it puts into pg_class.reltuples to try to represent the mean tuple density instead of the minimal density that actually prevails just after VACUUM. These changes alter the plans selected for certain regression tests, so update the expected files accordingly. (I removed join_1.out because it's not clear if it still applies; we can add back any variant versions as they are shown to be needed.)
2004-11-09Allow planner to fold "stable" functions to constants when formingTom Lane
selectivity estimates, per recent discussion.
2004-10-22In ALTER COLUMN TYPE, strip any implicit coercion operations appearingTom Lane
at the top level of the column's old default expression before adding an implicit coercion to the new column type. This seems to satisfy the principle of least surprise, as per discussion of bug #1290.
2004-10-07Fix problems with SQL functions returning rowtypes that have droppedTom Lane
columns. The returned tuple needs to have appropriate NULL columns inserted so that it actually matches the declared rowtype. It seemed convenient to use a JunkFilter for this, so I made some cleanups and simplifications in the JunkFilter code to allow it to support this additional functionality. (That in turn exposed a latent bug in nodeAppend.c, which is that it was returning a tuple slot whose descriptor didn't match its data.) Also, move check_sql_fn_retval out of pg_proc.c and into functions.c, where it seems to more naturally belong.
2004-10-02Clean up handling of inherited-table update queries, per bug reportTom Lane
from Sebastian Böck. The fix involves being more consistent about when rangetable entries are copied or modified. Someday we really need to fix this stuff to not scribble on its input data structures in the first place...
2004-10-01Fallout from changing index locking rules: we can reduce the strengthTom Lane
of locking used by REINDEX. REINDEX needs only ShareLock on the parent table, same as CREATE INDEX, plus an exclusive lock on the specific index being processed.
2004-08-29Pgindent run for 8.0.Bruce Momjian
2004-08-29Update copyright to 2004.Bruce Momjian
2004-08-19Repair some issues with column aliases and RowExpr construction in theTom Lane
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.
2004-08-17Standardize on the assumption that the arguments of a RowExpr correspondTom Lane
to the physical layout of the rowtype, ie, there are dummy arguments corresponding to any dropped columns in the rowtype. We formerly had a couple of places that did it this way and several others that did not. Fixes Gaetano Mendola's "cache lookup failed for type 0" bug of 5-Aug.
2004-08-04Label CVS tip as 8.0devel instead of 7.5devel. Adjust various commentsTom Lane
and documentation to reference 8.0 instead of 7.5.
2004-08-02Allow DECLARE CURSOR to take parameters from the portal in which it isTom Lane
executed. Previously, the DECLARE would succeed but subsequent FETCHes would fail since the parameter values supplied to DECLARE were not propagated to the portal created for the cursor. In support of this, add type Oids to ParamListInfo entries, which seems like a good idea anyway since code that extracts a value can double-check that it got the type of value it was expecting. Oliver Jowett, with minor editorialization by Tom Lane.
2004-06-11When using extended-query protocol, postpone planning of unnamed statementsTom Lane
until Bind is received, so that actual parameter values are visible to the planner. Make use of the parameter values for estimation purposes (but don't fold them into the actual plan). This buys back most of the potential loss of plan quality that ensues from using out-of-line parameters instead of putting literal values right into the query text. This patch creates a notion of constant-folding expressions 'for estimation purposes only', in which case we can be more aggressive than the normal eval_const_expressions() logic can be. Right now the only difference in behavior is inserting bound values for Params, but it will be interesting to look at other possibilities. One that we've seen come up repeatedly is reducing now() and related functions to current values, so that queries like ... WHERE timestampcol > now() - '1 day' have some chance of being planned effectively. Oliver Jowett, with some kibitzing from Tom Lane.
2004-06-09Support assignment to subfields of composite columns in UPDATE and INSERT.Tom Lane
As a side effect, cause subscripts in INSERT targetlists to do something more or less sensible; previously we evaluated such subscripts and then effectively ignored them. Another side effect is that UPDATE-ing an element or slice of an array value that is NULL now produces a non-null result, namely an array containing just the assigned-to positions.
2004-06-05Tweak palloc/repalloc to allow zero bytes to be requested, as per recentTom Lane
proposal. Eliminate several dozen now-unnecessary hacks to avoid palloc(0). (It's likely there are more that I didn't find.)
2004-06-05Make the world very nearly safe for composite-type columns in tables.Tom Lane
1. Solve the problem of not having TOAST references hiding inside composite values by establishing the rule that toasting only goes one level deep: a tuple can contain toasted fields, but a composite-type datum that is to be inserted into a tuple cannot. Enforcing this in heap_formtuple is relatively cheap and it avoids a large increase in the cost of running the tuptoaster during final storage of a row. 2. Fix some interesting problems in expansion of inherited queries that reference whole-row variables. We never really did this correctly before, but it's now relatively painless to solve by expanding the parent's whole-row Var into a RowExpr() selecting the proper columns from the child. If you dike out the preventive check in CheckAttributeType(), composite-type columns now seem to actually work. However, we surely cannot ship them like this --- without I/O for composite types, you can't get pg_dump to dump tables containing them. So a little more work still to do.
2004-06-01Just about there on de-FastList-ification.Tom Lane
2004-06-01Desultory de-FastList-ification. RelOptInfo.reltargetlist is back toTom Lane
being a plain List.
2004-05-30Use the new List API function names throughout the backend, and disable theNeil Conway
list compatibility API by default. While doing this, I decided to keep the llast() macro around and introduce llast_int() and llast_oid() variants.
2004-05-26Reimplement the linked list data structure used throughout the backend.Neil Conway
In the past, we used a 'Lispy' linked list implementation: a "list" was merely a pointer to the head node of the list. The problem with that design is that it makes lappend() and length() linear time. This patch fixes that problem (and others) by maintaining a count of the list length and a pointer to the tail node along with each head node pointer. A "list" is now a pointer to a structure containing some meta-data about the list; the head and tail pointers in that structure refer to ListCell structures that maintain the actual linked list of nodes. The function names of the list API have also been changed to, I hope, be more logically consistent. By default, the old function names are still available; they will be disabled-by-default once the rest of the tree has been updated to use the new API names.
2004-05-10Promote row expressions to full-fledged citizens of the expression syntax,Tom Lane
rather than allowing them only in a few special cases as before. In particular you can now pass a ROW() construct to a function that accepts a rowtype parameter. Internal generation of RowExprs fixes a number of corner cases that used to not work very well, such as referencing the whole-row result of a JOIN or subquery. This represents a further step in the work I started a month or so back to make rowtype values into first-class citizens.
2004-04-25Remove the last traces of Joe Hellerstein's "xfunc" optimization. PatchNeil Conway
from Alvaro Herrera. Also, removed lispsort.c, since it is no longer used.
2004-04-02check_sql_fn_retval has always thought that we supported doingTom Lane
'SELECT foo()' in a SQL function returning a rowtype, to simply pass back the results of another function returning the same rowtype. However, that hasn't actually worked in many years. Now it works again.
2004-04-02Get rid of crocky use of RangeVar nodes in parser to represent partiallyTom Lane
transformed whole-row variables. Cleaner to use regular whole-row Vars.
2004-03-29Use fuzzy comparison of path costs in add_path(), so that paths with theTom Lane
same path keys and nearly equivalent costs will be considered redundant. The exact nature of the fuzziness may get adjusted later based on current discussions, but no one has shot a hole in the basic idea yet ...
2004-03-24Replace max_expr_depth parameter with a max_stack_depth parameter thatTom Lane
is measured in kilobytes and checked against actual physical execution stack depth, as per my proposal of 30-Dec. This gives us a fairly bulletproof defense against crashing due to runaway recursive functions.
2004-03-21Revise syntax-error reporting behavior to give pleasant results forTom Lane
errors in internally-generated queries, such as those submitted by plpgsql functions. Per recent discussions with Fabien Coelho.
2004-03-17Reimplement CASE val WHEN compval1 THEN ... WHEN compval2 THEN ... ENDTom Lane
so that the 'val' is computed only once, per recent discussion. The speedup is not much when 'val' is just a simple variable, but could be significant for larger expressions. More importantly this avoids issues with multiple evaluations of a volatile 'val', and it allows the CASE expression to be reverse-listed in its original form by ruleutils.c.
2004-03-14Tweak planner so that index expressions and predicates are matched toTom Lane
queries without regard to whether coercions are stated explicitly or implicitly. Per suggestion from Stephan Szabo.
2004-03-02Teach is_distinct_query to recognize that GROUP BY forces a subquery'sTom Lane
output to be distinct, if all the GROUP BY columns appear in the output. Per suggestion from Dennis Haney.
2004-02-27Adjust remove_redundant_join_clauses() so that when it has a choiceTom Lane
of which redundant clause to remove, it removes the more expensive one. In simple scenarios the clauses will be like 'var = var' and there's no difference, but we are now capable of considering cases where there are sub-selects in the clauses, and it makes a BIG difference.
2004-02-17Make use of statistics on index expressions. There are still someTom Lane
corner cases that could stand improvement, but it does all the basic stuff. A byproduct is that the selectivity routines are no longer constrained to working on simple Vars; we might in future be able to improve the behavior for subexpressions that don't match indexes.
2004-02-03Rename SortMem and VacuumMem to work_mem and maintenance_work_mem.Tom Lane
Make btree index creation and initial validation of foreign-key constraints use maintenance_work_mem rather than work_mem as their memory limit. Add some code to guc.c to allow these variables to be referenced by their old names in SHOW and SET commands, for backwards compatibility.
2004-01-28simplify_function() mustn't try to evaluate functions that returnTom Lane
composite types, because TupleTableSlots aren't Datums and can't be stored in Const nodes. We can remove this restriction if we ever adopt a cleaner runtime representation for whole-tuple results, but at the moment it's broken. Per example from Thomas Hallgren.
2004-01-19Recognize that IN subqueries return already-unique results if they useTom Lane
UNION/INTERSECT/EXCEPT (without ALL). This adds on to the previous optimization for subqueries using DISTINCT.
2004-01-12Preserve AND/OR flatness during eval_const_expressions(). This seems aTom Lane
useful improvement in any case, and it keeps the new logic for restrictinfo structures happy. Per report from Kris Jurka.
2004-01-10Improve has_nullable_targetlist() to allow strict functions of simpleTom Lane
variables, not just simple variables. This was foreseen in the original coding of this routine, but not implemented until now. Responds to performance gripe from Laurent Perez.
2004-01-07More janitorial work: remove the explicit casting of NULL literals to aNeil Conway
pointer type when it is not necessary to do so. For future reference, casting NULL to a pointer type is only necessary when (a) invoking a function AND either (b) the function has no prototype OR (c) the function is a varargs function.
2004-01-05Adjust indexscan planning logic to keep RestrictInfo nodes associatedTom Lane
with index qual clauses in the Path representation. This saves a little work during createplan and (probably more importantly) allows reuse of cached selectivity estimates during indexscan planning. Also fix latent bug: wrong plan would have been generated for a 'special operator' used in a nestloop-inner-indexscan join qual, because the special operator would not have gotten into the list of quals to recheck. This bug is only latent because at present the special-operator code could never trigger on a join qual, but sooner or later someone will want to do it.
2004-01-05Improve UniquePath logic to detect the case where the input is alreadyTom Lane
known unique (eg, it is a SELECT DISTINCT ... subquery), and not do a redundant unique-ification step.
2004-01-05Add the ability to extract OR indexscan conditions from OR-of-ANDTom Lane
join conditions in which each OR subclause includes a constraint on the same relation. This implements the other useful side-effect of conversion to CNF format, without its unpleasant side-effects. As per pghackers discussion of a few weeks ago.
2004-01-04Merge restrictlist_selectivity into clauselist_selectivity byTom Lane
teaching the latter to accept either RestrictInfo nodes or bare clause expressions; and cache the selectivity result in the RestrictInfo node when possible. This extends the caching behavior of approx_selectivity to many more contexts, and should reduce duplicate selectivity calculations.
2004-01-04Rewrite OR indexscan processing to be more flexible. We can now for theTom Lane
first time generate an OR indexscan for a two-column index when the WHERE condition is like 'col1 = foo AND (col2 = bar OR col2 = baz)' --- before, the OR had to be on the first column of the index or we'd not notice the possibility of using it. Some progress towards extracting OR indexscans from subclauses of an OR that references multiple relations, too, although this code is #ifdef'd out because it needs more work.
2003-12-30Adjust the definition of RestrictInfo's left_relids and right_relidsTom Lane
fields: now they are valid whenever the clause is a binary opclause, not only when it is a potential join clause (there is a new boolean field canjoin to signal the latter condition). This lets us avoid recomputing the relid sets over and over while examining indexes. Still more work to do to make this as useful as it could be, because there are places that could use the info but don't have access to the RestrictInfo node.
2003-12-28Clean up the usage of canonicalize_qual(): in particular, be consistentTom Lane
about whether it is applied before or after eval_const_expressions(). I believe there were some corner cases where the system would fail to recognize that a partial index is applicable because of the previous inconsistency. Store normal rather than 'implicit AND' representations of constraints and index predicates in the catalogs. initdb forced due to representation change of constraints/predicates.
2003-12-09query_tree_mutator should copy RangeTblEntry nodes even when it's notTom Lane
planning to modify them itself. Otherwise we end up with shared RTE substructure, which breaks inheritance_planner because the rte->inh flag needs to be independent in each copied subquery. Per bug report from Chris Piker.