to the target list in gram.y; it must wait till after expansion of the
target list in analyze.c. Per bug report 4-Nov:
lx=# CREATE TABLE abc (a char, b char, c char);
CREATE
lx=# CREATE TABLE xyz (x, y, z) AS SELECT * FROM abc;
ERROR: CREATE TABLE/AS SELECT has mismatched column count
Modified the parser and the SET handlers to use full Node structures
rather than simply a character string argument.
Implement INTERVAL() YEAR TO MONTH (etc) syntax per SQL99.
Does not yet accept the goofy string format that goes along with, but
this should be fairly straight forward to fix now as a bug or later
as a feature.
Implement precision for the INTERVAL() type.
Use the typmod mechanism for both of INTERVAL features.
Fix the INTERVAL syntax in the parser:
opt_interval was in the wrong place.
INTERVAL is now a reserved word, otherwise we get reduce/reduce errors.
Implement an explicit date_part() function for TIMETZ.
Should fix coersion problem with INTERVAL reported by Peter E.
Fix up some error messages for date/time types.
Use all caps for type names within message.
Fix recently introduced side-effect bug disabling 'epoch' as a recognized
field for date_part() etc. Reported by Peter E. (??)
Bump catalog version number.
Rename "microseconds" current transaction time field
from ...Msec to ...Usec. Duh!
date/time regression tests updated for reference platform, but a few
changes will be necessary for others.
pgsql-hackers. pg_opclass now has a row for each opclass supported by each
index AM, not a row for each opclass name. This allows pg_opclass to show
directly whether an AM supports an opclass, and furthermore makes it possible
to store additional information about an opclass that might be AM-dependent.
pg_opclass and pg_amop now store "lossy" and "haskeytype" information that we
previously expected the user to remember to provide in CREATE INDEX commands.
Lossiness is no longer an index-level property, but is associated with the
use of a particular operator in a particular index opclass.
Along the way, IndexSupportInitialize now uses the syscaches to retrieve
pg_amop and pg_amproc entries. I find this reduces backend launch time by
about ten percent, at the cost of a couple more special cases in catcache.c's
IndexScanOK.
Initial work by Oleg Bartunov and Teodor Sigaev, further hacking by Tom Lane.
initdb forced.
has an alias SERIAL4 and a sister SERIAL8. SERIAL8 is just the same
except the created column is type int8 not int4.
initdb forced. Note this also breaks any chance of pg_upgrade from 7.1,
unless we hack up pg_upgrade to drop and recreate sequences. (Which is
not out of the question, but I don't wanna do it.)
default, but OIDS are removed from many system catalogs that don't need them.
Some interesting side effects: TOAST pointers are 20 bytes not 32 now;
pg_description has a three-column key instead of one.
Bugs fixed in passing: BINARY cursors work again; pg_class.relhaspkey
has some usefulness; pg_dump dumps comments on indexes, rules, and
triggers in a valid order.
initdb forced.
USER and ALTER USER to appear in any order, not only the fixed order
they used to be required to appear in.
Also, some changes from Tom Lane to create a FULL option for VACUUM;
it doesn't do anything yet, but I needed to change many of the same
files to make that happen, so now seemed like a good time.
tests to return the correct results per SQL9x when given NULL inputs.
Reimplement these tests as well as IS [NOT] NULL to have their own
expression node types, instead of depending on special functions.
From Joe Conway, with a little help from Tom Lane.
for GRANT/REVOKE is now just that, not "CHANGE".
On the way, migrate some of the aclitem internal representation away from
the parser and build a real parse tree instead. Also add some 'const'
qualifiers.
of costsize.c routines to pass Query root, so that costsize can figure
more things out by itself and not be so dependent on its callers to tell
it everything it needs to know. Use selectivity of hash or merge clause
to estimate number of tuples processed internally in these joins
(this is more useful than it would've been before, since eqjoinsel is
somewhat more accurate than before).
create_index_paths are not immediately discarded, but are available for
subsequent planner work. This allows avoiding redundant syscache lookups
in several places. Change interface to operator selectivity estimation
procedures to allow faster and more flexible estimation.
Initdb forced due to change of pg_proc entries for selectivity functions!
a separate statement (though it can still be invoked as part of VACUUM, too).
pg_statistic redesigned to be more flexible about what statistics are
stored. ANALYZE now collects a list of several of the most common values,
not just one, plus a histogram (not just the min and max values). Random
sampling is used to make the process reasonably fast even on very large
tables. The number of values and histogram bins collected is now
user-settable via an ALTER TABLE command.
There is more still to do; the new stats are not being used everywhere
they could be in the planner. But the remaining changes for this project
should be localized, and the behavior is already better than before.
A not-very-related change is that sorting now makes use of btree comparison
routines if it can find one, rather than invoking '<' twice.
and revert documentation to describe the existing INHERITS clause
instead, per recent discussion in pghackers. Also fix implementation
of SQL_inheritance SET variable: it is not cool to look at this var
during the initial parsing phase, only during parse_analyze(). See
recent bug report concerning misinterpretation of date constants just
after a SET TIMEZONE command. gram.y really has to be an invariant
transformation of the query string to a raw parsetree; anything that
can vary with time must be done during parse analysis.
comparison does not consider paths different when they differ only in
uninteresting aspects of sort order. (We had a special case of this
consideration for indexscans already, but generalize it to apply to
ordered join paths too.) Be stricter about what is a canonical pathkey
to allow faster pathkey comparison. Cache canonical pathkeys and
dispersion stats for left and right sides of a RestrictInfo's clause,
to avoid repeated computation. Total speedup will depend on number of
tables in a query, but I see about 4x speedup of planning phase for
a sample seven-table query.
avoid repeated evaluations in cost_qual_eval(). This turns out to save
a useful fraction of planning time. No change to external representation
of RestrictInfo --- although that node type doesn't appear in stored
rules anyway.
cloned, rather than always cloning template1. Modify initdb to generate
two identical databases rather than one, template0 and template1.
Connections to template0 are disallowed, so that it will always remain
in its virgin as-initdb'd state. pg_dumpall now dumps databases with
restore commands that say CREATE DATABASE foo WITH TEMPLATE = template0.
This allows proper behavior when there is user-added data in template1.
initdb forced!
joins, and clean things up a good deal at the same time. Append plan node
no longer hacks on rangetable at runtime --- instead, all child tables are
given their own RT entries during planning. Concept of multiple target
tables pushed up into execMain, replacing bug-prone implementation within
nodeAppend. Planner now supports generating Append plans for inheritance
sets either at the top of the plan (the old way) or at the bottom. Expanding
at the bottom is appropriate for tables used as sources, since they may
appear inside an outer join; but we must still expand at the top when the
target of an UPDATE or DELETE is an inheritance set, because we actually need
a different targetlist and junkfilter for each target table in that case.
Fortunately a target table can't be inside an outer join... Bizarre mutual
recursion between union_planner and prepunion.c is gone --- in fact,
union_planner doesn't really have much to do with union queries anymore,
so I renamed it grouping_planner.
position() and substring() functions, so that it works transparently for
bit types as well. Alias the text functions appropriately.
Add position() for bit types.
Add new constant node T_BitString that represents literals of the form
B'1001 and pass those to zpbit type.
This patch forces the use of 'DROP VIEW' to destroy views.
It also changes the syntax of DROP VIEW to
DROP VIEW v1, v2, ...
to match the syntax of DROP TABLE.
Some error messages were changed so this patch also includes changes to the
appropriate expected/*.out files.
Doc changes for 'DROP TABLE" and 'DROP VIEW' are included.
--
Mark Hollomon
took some rejiggering of typename and ACL parsing, as well as moving
parse_analyze call out of parser(). Restructure postgres.c processing
so that parse analysis and rewrite are skipped when in abort-transaction
state. Only COMMIT and ABORT statements will be processed beyond the raw
parser() phase. This addresses problem of parser failing with database access
errors while in aborted state (see pghackers discussions around 7/28/00).
Also fix some bugs with COMMIT/ABORT statements appearing in the middle of
a single query input string.
Function, operator, and aggregate arguments/results can now use full
TypeName production, in particular foo[] for array types.
DROP OPERATOR and COMMENT ON OPERATOR were broken for unary operators.
Allow CREATE AGGREGATE to accept unquoted numeric constants for initcond.
SQL92 semantics, including support for ALL option. All three can be used
in subqueries and views. DISTINCT and ORDER BY work now in views, too.
This rewrite fixes many problems with cross-datatype UNIONs and INSERT/SELECT
where the SELECT yields different datatypes than the INSERT needs. I did
that by making UNION subqueries and SELECT in INSERT be treated like
subselects-in-FROM, thereby allowing an extra level of targetlist where the
datatype conversions can be inserted safely.
INITDB NEEDED!
(Don't forget that an alias is required.) Views reimplemented as expanding
to subselect-in-FROM. Grouping, aggregates, DISTINCT in views actually
work now (he says optimistically). No UNION support in subselects/views
yet, but I have some ideas about that. Rule-related permissions checking
moved out of rewriter and into executor.
INITDB REQUIRED!
including utility statements. Still can't copy or compare executor
state, but at present that doesn't seem to be necessary. This makes
it possible to execute most (all?) utility statements in plpgsql.
Had to change parsetree representation of CreateTrigStmt so that it
contained only legal Nodes, and not bare string constants.
from Param nodes, per discussion a few days ago on pghackers. Add new
expression node type FieldSelect that implements the functionality where
it's actually needed. Clean up some other unused fields in Func nodes
as well.
NOTE: initdb forced due to change in stored expression trees for rules.
There's now only one transition value and transition function.
NULL handling in aggregates is a lot cleaner. Also, use Numeric
accumulators instead of integer accumulators for sum/avg on integer
datatypes --- this avoids overflow at the cost of being a little slower.
Implement VARIANCE() and STDDEV() aggregates in the standard backend.
Also, enable new LIKE selectivity estimators by default. Unrelated
change, but as long as I had to force initdb anyway...
memory contexts. Currently, only leaks in expressions executed as
quals or projections are handled. Clean up some old dead cruft in
executor while at it --- unused fields in state nodes, that sort of thing.
in copyfuncs and equalfuncs exposed by regression tests. We still have
some work to do: these modules really ought to handle most or all of
the utility statement node types. But it's better than it was.
costs using the inner path's parent->rows count as the number of tuples
processed per inner scan iteration. This is wrong when we are using an
inner indexscan with indexquals based on join clauses, because the rows
count in a Relation node reflects the selectivity of the restriction
clauses for that rel only. Upshot was that if join clause was very
selective, we'd drastically overestimate the true cost of the join.
Fix is to calculate correct output-rows estimate for an inner indexscan
when the IndexPath node is created and save it in the path node.
Change of path node doesn't require initdb, since path nodes don't
appear in saved rules.
integers) to be strings instead of 'double'. We convert from string form
to internal representation only after type resolution has determined the
correct type for the constant. This eliminates loss-of-precision worries
and gets rid of the change in behavior seen at 17 digits with the
previous kluge.
represent the result of a binary-compatible type coercion. At runtime
it just evaluates its argument --- but during type resolution, exprType
will pick up the output type of the RelabelType node instead of the type
of the argument. This solves some longstanding problems with dropped
type coercions, an example being 'select now()::abstime::int4' which
used to produce date-formatted output, not an integer, because the
coercion to int4 was dropped on the floor.
accesses versus sequential accesses, a (very crude) estimate of the
effects of caching on random page accesses, and cost to evaluate WHERE-
clause expressions. Export critical parameters for this model as SET
variables. Also, create SET variables for the planner's enable flags
(enable_seqscan, enable_indexscan, etc) so that these can be controlled
more conveniently than via PGOPTIONS.
Planner now estimates both startup cost (cost before retrieving
first tuple) and total cost of each path, so it can optimize queries
with LIMIT on a reasonable basis by interpolating between these costs.
Same facility is a win for EXISTS(...) subqueries and some other cases.
Redesign pathkey representation to achieve a major speedup in planning
(I saw as much as 5X on a 10-way join); also minor changes in planner
to reduce memory consumption by recycling discarded Path nodes and
not constructing unnecessary lists.
Minor cleanups to display more-plausible costs in some cases in
EXPLAIN output.
Initdb forced by change in interface to index cost estimation
functions.
SELECT a FROM t1 tx (a);
Allow join syntax, including queries like
SELECT * FROM t1 NATURAL JOIN t2;
Update RTE structure to hold column aliases in an Attr structure.
fields in JoinPaths --- turns out that we do need that after all :-(.
Also, rearrange planner so that only one RelOptInfo is created for a
particular set of joined base relations, no matter how many different
subsets of relations it can be created from. This saves memory and
processing time compared to the old method of making a bunch of RelOptInfos
and then removing the duplicates. Clean up the jointree iteration logic;
not sure if it's better, but I sure find it more readable and plausible
now, particularly for the case of 'bushy plans'.
Tom Lane