practice of evaluating MemSet's arguments multiple times, except for
the special case of newNode(), where we can assume the argument is
a constant sizeof() operator.
Also, add GetMemoryChunkContext() to mcxt.c's API, in preparation for
fixing recent GEQO breakage.
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.
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.
documentation and regression test mods. It seemed small and unobtrusive enough
to not require a specific proposal on the hackers list -- but if not, let me
know and I'll make a pitch. Otherwise, if there are no objections please apply.
Joe Conway
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.
('SELECT expression') inline, like macros, during the constant-folding
phase of planning. The actual expansion is not difficult, but checking
that we're not changing the semantics of the call turns out to be more
subtle than one might think; in particular must pay attention to
permissions issues, strictness, and volatility.
-hackers a couple days ago.
Notes/caveats:
- added regression tests for the new functionality, all
regression tests pass on my machine
- added pg_dump support
- updated PL/PgSQL to support per-statement triggers; didn't
look at the other procedural languages.
- there's (even) more code duplication in trigger.c than there
was previously. Any suggestions on how to refactor the
ExecXXXTriggers() functions to reuse more code would be
welcome -- I took a brief look at it, but couldn't see an
easy way to do it (there are several subtly-different
versions of the code in question)
- updated the documentation. I also took the liberty of
removing a big chunk of duplicated syntax documentation in
the Programmer's Guide on triggers, and moving that
information to the CREATE TRIGGER reference page.
- I also included some spelling fixes and similar small
cleanups I noticed while making the changes. If you'd like
me to split those into a separate patch, let me know.
Neil Conway
of groups produced by GROUP BY. This improves the accuracy of planning
estimates for grouped subselects, and is needed to check whether a
hashed aggregation plan risks memory overflow.
precision for float4, float8, and geometric types. Set it in pg_dump
so that float data can be dumped/reloaded exactly (at least on platforms
where the float I/O support is properly implemented). Initial patch by
Pedro Ferreira, some additional work by Tom Lane.
now)" item on the open items, and subsequent plpgsql function I sent in,
made me realize it was too hard to get the upper and lower bound of an
array. The attached creates two functions that I think will be very
useful when combined with the ability of plpgsql to return sets.
array_lower(array, dim_num)
- and -
array_upper(array, dim_num)
They return the value (as an int) of the upper and lower bound of the
requested dim in the provided array.
Joe Conway
where it's safe to do database access. Along the way, fix core dump
for 'DEFAULT' parameters to CREATE DATABASE. initdb forced due to
change in pg_proc entry.
Ray Ontko 28-June-02. Also, fix prefix_selectivity for NAME lefthand
variables (it was bogusly assuming binary compatibility), and adjust
make_greater_string() to not call pg_mbcliplen() with invalid multibyte
data (this last per bug report that I can't find at the moment, but it
was in July '02).
specifically ceil(), floor(), and sign(). There may be other functions
that need to be added, but this is a start. I've included some simple
regression tests.
Neil Conway
so that precision of result is always at least as good as you'd get from
float8 arithmetic (ie, always at least 16 digits of accuracy). Per
pg_hackers discussion a few days ago.
the SQL99 standard. (I'm not sure that the character-class features are
quite right, but that can be fixed later.) Document SQL99 and POSIX
regexps as being different features; provide variants of SUBSTRING for
each.
composite types. Add a couple more lsyscache.c routines to support this,
and make use of them in some other places that were doing lookups the
hard way.
ruleutils display is not such a great idea. For arguments of functions
and operators I think we'd better keep the historical behavior of showing
such casts explicitly, to ensure that the function/operator is reparsed
the same way when the rule is reloaded. This also makes the output of
EXPLAIN less obscurantist about exactly what's happening.
to be flexible about assignment casts without introducing ambiguity in
operator/function resolution. Introduce a well-defined promotion hierarchy
for numeric datatypes (int2->int4->int8->numeric->float4->float8).
Change make_const to initially label numeric literals as int4, int8, or
numeric (never float8 anymore).
Explicitly mark Func and RelabelType nodes to indicate whether they came
from a function call, explicit cast, or implicit cast; use this to do
reverse-listing more accurately and without so many heuristics.
Explicit casts to char, varchar, bit, varbit will truncate or pad without
raising an error (the pre-7.2 behavior), while assigning to a column without
any explicit cast will still raise an error for wrong-length data like 7.3.
This more nearly follows the SQL spec than 7.2 behavior (we should be
reporting a 'completion condition' in the explicit-cast cases, but we have
no mechanism for that, so just do silent truncation).
Fix some problems with enforcement of typmod for array elements;
it didn't work at all in 'UPDATE ... SET array[n] = foo', for example.
Provide a generalized array_length_coerce() function to replace the
specialized per-array-type functions that used to be needed (and were
missing for NUMERIC as well as all the datetime types).
Add missing conversions int8<->float4, text<->numeric, oid<->int8.
initdb forced.
> src/backend/optimizer/path/indxpath.c; see the "special indexable
> operators" stuff near the bottom of that file. (It's a bit of a crock
> that this code is hardwired there, and not somehow accessed through a
> system catalog, but it's what we've got at the moment.)
The attached patch re-enables a bytea right hand argument (as compared
to a text right hand argument), and enables index usage, for bytea LIKE
Joe Conway
pointed out by Barry Lind: UPDATE bigintcol = 10000000000 fails because
the constant is initially taken as float8. We really need a better way,
but it's not gonna happen for 7.3.
Also, remove int4reltime() function, which is redundant with the
existing binary-compatibility coercion path from int4 to reltime,
and probably has been unreachable code for a long while.
type for runtime constraint checks, instead of misusing the parse-time
Constraint node for the purpose. Fix some damage introduced into type
coercion logic; in particular ensure that a coerced expression tree will
read out the correct result type when inspected (patch had broken some
RelabelType cases). Enforce domain NOT NULL constraints against columns
that are omitted from an INSERT.
array header, and to compute sizing and alignment of array elements
the same way normal tuple access operations do --- viz, using the
tupmacs.h macros att_addlength and att_align. This makes the world
safe for arrays of cstrings or intervals, and should make it much
easier to write array-type-polymorphic functions; as examples see
the cleanups of array_out and contrib/array_iterator. By Joe Conway
and Tom Lane.
replace(string, from, to)
-- replaces all occurrences of "from" in "string" to "to"
split(string, fldsep, column)
-- splits "string" on "fldsep" and returns "column" number piece
to_hex(int32_num) & to_hex(int64_num)
-- takes integer number and returns as hex string
Joe Conway
with OPAQUE, as per recent pghackers discussion. I still want to do some
more work on the 'cstring' pseudo-type, but I'm going to commit the bulk
of the changes now before the tree starts shifting under me ...
> Quick system function to pull out the current database.
>
> I've used this a number of times to allow stored procedures to find out
> where they are. Especially useful for those that do logging or hit a
> remote server.
>
> It's called current_database() to match with current_user().
It's also a necessity for an informational schema. The catalog
(database) name is required in a number of places.
Rod Taylor
sets of triggers. Also modify psql \d command to show foreign key
constraints as such and hide the triggers. pg_get_constraintdef()
function added to backend to support these. From Rod Taylor, code
review and some editorialization by Tom Lane.
composite type capability makes it possible to create a system view
based on a table function in a way that is hopefully palatable to
everyone. The attached patch takes advantage of this, moving
show_all_settings() from contrib/tablefunc into the backend (renamed
all_settings(). It is defined as a builtin returning type RECORD. During
initdb a system view is created to expose the same information presently
available through SHOW ALL. For example:
test=# select * from pg_settings where name like '%debug%';
name | setting
-----------------------+---------
debug_assertions | on
debug_pretty_print | off
debug_print_parse | off
debug_print_plan | off
debug_print_query | off
debug_print_rewritten | off
wal_debug | 0
(7 rows)
Additionally during initdb two rules are created which make it possible
to change settings by updating the system view -- a "virtual table" as
Tom put it. Here's an example:
Joe Conway
to make a reasonable attempt at accounting for palloc overhead, not just
the requested size of each memory chunk. Since in many scenarios this
will make for a significant reduction in the amount of space acquired,
partially compensate by doubling the default value of SORT_MEM to 1Mb.
Per discussion in pgsql-general around 9-Jun-2002..
has_language_privilege, has_schema_privilege to let SQL queries test
all the new privilege types in 7.3. Also, add functions pg_table_is_visible,
pg_type_is_visible, pg_function_is_visible, pg_operator_is_visible,
pg_opclass_is_visible to test whether objects contained in schemas are
visible in the current search path. Do some minor cleanup to centralize
accesses to pg_database, as well.
The local buffer manager is no longer used for newly-created relations
(unless they are TEMP); a new non-TEMP relation goes through the shared
bufmgr and thus will participate normally in checkpoints. But TEMP relations
use the local buffer manager throughout their lifespan. Also, operations
in TEMP relations are not logged in WAL, thus improving performance.
Since it's no longer necessary to fsync relations as they move out of the
local buffers into shared buffers, quite a lot of smgr.c/md.c/fd.c code
is no longer needed and has been removed: there's no concept of a dirty
relation anymore in md.c/fd.c, and we never fsync anything but WAL.
Still TODO: improve local buffer management algorithms so that it would
be reasonable to increase NLocBuffer.
