185 Commits

Author SHA1 Message Date
Tom Lane
12b1b5d837 Instead of supposing (wrongly, in the general case) that the rowtype
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.
2004-12-11 23:26:51 +00:00
Tom Lane
9a633cbb6c Allow planner to fold "stable" functions to constants when forming
selectivity estimates, per recent discussion.
2004-11-09 21:42:53 +00:00
Tom Lane
9309d5f2ba In ALTER COLUMN TYPE, strip any implicit coercion operations appearing
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.
2004-10-22 17:20:05 +00:00
Tom Lane
a8487e15ed Fix problems with SQL functions returning rowtypes that have dropped
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.
2004-10-07 18:38:51 +00:00
Tom Lane
47aa95e951 Clean up handling of inherited-table update queries, per bug report
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...
2004-10-02 22:39:49 +00:00
Bruce Momjian
b6b71b85bc Pgindent run for 8.0. 2004-08-29 05:07:03 +00:00
Bruce Momjian
da9a8649d8 Update copyright to 2004. 2004-08-29 04:13:13 +00:00
Tom Lane
fcaad7e2c1 Standardize on the assumption that the arguments of a RowExpr correspond
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.
2004-08-17 18:47:09 +00:00
Tom Lane
f622c54049 Allow DECLARE CURSOR to take parameters from the portal in which it is
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.
2004-08-02 01:30:51 +00:00
Tom Lane
7643bed58e When using extended-query protocol, postpone planning of unnamed statements
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.
2004-06-11 01:09:22 +00:00
Tom Lane
7e64dbc6b5 Support assignment to subfields of composite columns in UPDATE and INSERT.
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.
2004-06-09 19:08:20 +00:00
Tom Lane
c3a153afed Tweak palloc/repalloc to allow zero bytes to be requested, as per recent
proposal.  Eliminate several dozen now-unnecessary hacks to avoid palloc(0).
(It's likely there are more that I didn't find.)
2004-06-05 19:48:09 +00:00
Tom Lane
e590ceecf1 Just about there on de-FastList-ification. 2004-06-01 04:47:46 +00:00
Neil Conway
72b6ad6313 Use the new List API function names throughout the backend, and disable the
list compatibility API by default. While doing this, I decided to keep
the llast() macro around and introduce llast_int() and llast_oid() variants.
2004-05-30 23:40:41 +00:00
Neil Conway
d0b4399d81 Reimplement the linked list data structure used throughout the backend.
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.
2004-05-26 04:41:50 +00:00
Tom Lane
2f63232d30 Promote row expressions to full-fledged citizens of the expression syntax,
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.
2004-05-10 22:44:49 +00:00
Tom Lane
8efbe30df5 check_sql_fn_retval has always thought that we supported doing
'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.
2004-04-02 23:14:08 +00:00
Tom Lane
27a4f06ade Get rid of crocky use of RangeVar nodes in parser to represent partially
transformed whole-row variables.  Cleaner to use regular whole-row Vars.
2004-04-02 19:07:02 +00:00
Tom Lane
8899a2aba9 Replace max_expr_depth parameter with a max_stack_depth parameter that
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.
2004-03-24 22:40:29 +00:00
Tom Lane
f938c2b91b Revise syntax-error reporting behavior to give pleasant results for
errors in internally-generated queries, such as those submitted by
plpgsql functions.  Per recent discussions with Fabien Coelho.
2004-03-21 22:29:11 +00:00
Tom Lane
55f7c3300d Reimplement CASE val WHEN compval1 THEN ... WHEN compval2 THEN ... END
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.
2004-03-17 20:48:43 +00:00
Tom Lane
04226b6404 Tweak planner so that index expressions and predicates are matched to
queries without regard to whether coercions are stated explicitly or
implicitly.  Per suggestion from Stephan Szabo.
2004-03-14 23:41:27 +00:00
Tom Lane
4405b3e05e simplify_function() mustn't try to evaluate functions that return
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.
2004-01-28 00:05:04 +00:00
Tom Lane
5590be0a9e Preserve AND/OR flatness during eval_const_expressions(). This seems a
useful improvement in any case, and it keeps the new logic for restrictinfo
structures happy.  Per report from Kris Jurka.
2004-01-12 20:48:15 +00:00
Tom Lane
a43f4307f7 Improve has_nullable_targetlist() to allow strict functions of simple
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.
2004-01-10 18:13:53 +00:00
Tom Lane
5c74ce23db Improve UniquePath logic to detect the case where the input is already
known unique (eg, it is a SELECT DISTINCT ... subquery), and not do a
redundant unique-ification step.
2004-01-05 18:04:39 +00:00
Tom Lane
82b4dd394f Merge restrictlist_selectivity into clauselist_selectivity by
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.
2004-01-04 03:51:52 +00:00
Tom Lane
be6c38b903 Adjust the definition of RestrictInfo's left_relids and right_relids
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.
2003-12-30 23:53:15 +00:00
Tom Lane
c607bd693f Clean up the usage of canonicalize_qual(): in particular, be consistent
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.
2003-12-28 21:57:37 +00:00
Tom Lane
2d83e7c73c query_tree_mutator should copy RangeTblEntry nodes even when it's not
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.
2003-12-09 01:56:20 +00:00
PostgreSQL Daemon
969685ad44 $Header: -> $PostgreSQL Changes ... 2003-11-29 19:52:15 +00:00
Tom Lane
a35deb5400 Give a useful error message if a RangeVar is encountered in an expression.
Per example from Ian Barwick, 28-Oct-03.
2003-10-29 18:10:15 +00:00
Tom Lane
e945246321 Fix ARRAY[] construct so that in multidimensional case, elements can
be anything yielding an array of the proper kind, not only sub-ARRAY[]
constructs; do subscript checking at runtime not parse time.  Also,
adjust array_cat to make array || array comply with the SQL99 spec.

Joe Conway
2003-08-17 23:43:27 +00:00
Bruce Momjian
46785776c4 Another pgindent run with updated typedefs. 2003-08-08 21:42:59 +00:00
Bruce Momjian
f3c3deb7d0 Update copyrights to 2003. 2003-08-04 02:40:20 +00:00
Bruce Momjian
089003fb46 pgindent run. 2003-08-04 00:43:34 +00:00
Tom Lane
455a55fc29 Tighten inline_function's test for overly complex parameters. This
should catch most situations where repeated inlining blows up the
expression complexity unreasonably, as in Joe Conway's recent example.
2003-08-03 23:46:37 +00:00
Tom Lane
aad71b40ca Add error stack traceback support for SQL-language functions. 2003-07-28 18:33:18 +00:00
Tom Lane
45708f5ebc Error message editing in backend/optimizer, backend/rewrite. 2003-07-25 00:01:09 +00:00
Tom Lane
b89140a7ec Do honest transformation and preprocessing of LIMIT/OFFSET clauses,
instead of the former kluge whereby gram.y emitted already-transformed
expressions.  This is needed so that Params appearing in these clauses
actually work correctly.  I suppose some might claim that the side effect
of 'SELECT ... LIMIT 2+2' working is a new feature, but I say this is
a bug fix.
2003-07-03 19:07:54 +00:00
Tom Lane
455891bf96 Code review for UPDATE tab SET col = DEFAULT patch ... whack it around
so it has some chance of working in rules ...
2003-07-03 16:34:26 +00:00
Tom Lane
02b5d8e371 Dept. of second thoughts: supporting inlining of polymorphic SQL functions
takes only a few more lines of code than preventing it, so might as well
support it.
2003-07-01 19:07:02 +00:00
Tom Lane
d6d07a0eea SQL functions can have arguments and results declared ANYARRAY or
ANYELEMENT.  The effect is to postpone typechecking of the function
body until runtime.  Documentation is still lacking.

Original patch by Joe Conway, modified to postpone type checking
by Tom Lane.
2003-07-01 00:04:39 +00:00
Tom Lane
bee217924d Support expressions of the form 'scalar op ANY (array)' and
'scalar op ALL (array)', where the operator is applied between the
lefthand scalar and each element of the array.  The operator must
yield boolean; the result of the construct is the OR or AND of the
per-element results, respectively.

Original coding by Joe Conway, after an idea of Peter's.  Rewritten
by Tom to keep the implementation strictly separate from subqueries.
2003-06-29 00:33:44 +00:00
Bruce Momjian
111d8e522b Back out array mega-patch.
Joe Conway
2003-06-25 21:30:34 +00:00
Bruce Momjian
46bf651480 Array mega-patch.
Joe Conway
2003-06-24 23:14:49 +00:00
Tom Lane
e649796f12 Implement outer-level aggregates to conform to the SQL spec, with
extensions to support our historical behavior.  An aggregate belongs
to the closest query level of any of the variables in its argument,
or the current query level if there are no variables (e.g., COUNT(*)).
The implementation involves adding an agglevelsup field to Aggref,
and treating outer aggregates like outer variables at planning time.
2003-06-06 15:04:03 +00:00
Tom Lane
8a6ac83dab Fix some planner performance problems with large WHERE clauses, by
introducing new 'FastList' list-construction subroutines to use in
hot spots.  This avoids the O(N^2) behavior of repeated lappend's
by keeping a tail pointer, while not changing behavior by reversing
list order as the lcons() method would do.
2003-05-28 22:32:50 +00:00
Tom Lane
fc8d970cbc Replace functional-index facility with expressional indexes. Any column
of an index can now be a computed expression instead of a simple variable.
Restrictions on expressions are the same as for predicates (only immutable
functions, no sub-selects).  This fixes problems recently introduced with
inlining SQL functions, because the inlining transformation is applied to
both expression trees so the planner can still match them up.  Along the
way, improve efficiency of handling index predicates (both predicates and
index expressions are now cached by the relcache) and fix 7.3 oversight
that didn't record dependencies of predicate expressions.
2003-05-28 16:04:02 +00:00
Tom Lane
aa282d4446 Infrastructure for deducing Param types from context, in the same way
that the types of untyped string-literal constants are deduced (ie,
when coerce_type is applied to 'em, that's what the type must be).
Remove the ancient hack of storing the input Param-types array as a
global variable, and put the info into ParseState instead.  This touches
a lot of files because of adjustment of routine parameter lists, but
it's really not a large patch.  Note: PREPARE statement still insists on
exact specification of parameter types, but that could easily be relaxed
now, if we wanted to do so.
2003-04-29 22:13:11 +00:00