expressions, ARRAY(sub-SELECT) expressions, some array functions.
Polymorphic functions using ANYARRAY/ANYELEMENT argument and return
types. Some regression tests in place, documentation is lacking.
Joe Conway, with some kibitzing from Tom Lane.
> =================================================================
> User interface proposal for multi-row function targetlist entries
> =================================================================
> 1. Only one targetlist entry may return a set.
> 2. Each targetlist item (other than the set returning one) is
> repeated for each item in the returned set.
>
Having gotten no objections (actually, no response at all), I can only
assume no one had heartburn with this change. The attached patch covers
the first of the two proposals, i.e. restricting the target list to only
one set returning function.
Joe Conway
> User interface proposal for multi-row function targetlist entries
> =================================================================
> 1. Only one targetlist entry may return a set.
> 2. Each targetlist item (other than the set returning one) is
> repeated for each item in the returned set.
>
Having gotten no objections (actually, no response at all), I can only assume
no one had heartburn with this change. The attached patch covers the first of
the two proposals, i.e. restricting the target list to only one set returning
function.
It compiles cleanly, and passes all regression tests. If there are no
objections, please apply.
Any suggestions on where this should be documented (other than maybe sql-select)?
Thanks,
Joe
p.s. Here's what the previous example now looks like:
CREATE TABLE bar(f1 int, f2 text, f3 int);
INSERT INTO bar VALUES(1, 'Hello', 42);
INSERT INTO bar VALUES(2, 'Happy', 45);
CREATE TABLE foo(a int, b text);
INSERT INTO foo VALUES(42, 'World');
INSERT INTO foo VALUES(42, 'Everyone');
INSERT INTO foo VALUES(45, 'Birthday');
INSERT INTO foo VALUES(45, 'New Year');
CREATE TABLE foo2(a int, b text);
INSERT INTO foo2 VALUES(42, '!!!!');
INSERT INTO foo2 VALUES(42, '????');
INSERT INTO foo2 VALUES(42, '####');
INSERT INTO foo2 VALUES(45, '$$$$');
CREATE OR REPLACE FUNCTION getfoo(int) RETURNS SETOF text AS '
SELECT b FROM foo WHERE a = $1
' language 'sql';
CREATE OR REPLACE FUNCTION getfoo2(int) RETURNS SETOF text AS '
SELECT b FROM foo2 WHERE a = $1
' language 'sql';
regression=# SELECT f1, f2, getfoo(f3) AS f4 FROM bar;
f1 | f2 | f4
----+-------+----------
1 | Hello | World
1 | Hello | Everyone
2 | Happy | Birthday
2 | Happy | New Year
(4 rows)
regression=# SELECT f1, f2, getfoo(f3) AS f4, getfoo2(f3) AS f5 FROM bar;
ERROR: Only one target list entry may return a set result
Joe Conway
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 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.
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.
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.
latent wrong-struct-type bugs and makes the coding style more uniform,
since the majority of places working with lists of column names were
already using Strings not Idents. While at it, remove vestigial
support for Stream node type, and otherwise-unreferenced nodes.h entries
for T_TupleCount and T_BaseNode.
NB: full recompile is recommended due to changes of Node type numbers.
This shouldn't force an initdb though.
to behave according to SQL92 (or according to my current understanding
of same, anyway). Per pghackers discussion way back in March 2002:
thread 'Do FROM items of different schemas conflict?'
code review by Tom Lane. Remaining issues: functions that take or
return tuple types are likely to break if one drops (or adds!)
a column in the table defining the type. Need to think about what
to do here.
Along the way: some code review for recent COPY changes; mark system
columns attnotnull = true where appropriate, per discussion a month ago.
entries, per pghackers discussion. This fixes aggregates to live in
namespaces, and also simplifies/speeds up lookup in parse_func.c.
Also, add a 'proimplicit' flag to pg_proc that controls whether a type
coercion function may be invoked implicitly, or only explicitly. The
current settings of these flags are more permissive than I would like,
but we will need to debate and refine the behavior; for now, I avoided
breaking regression tests as much as I could.
addRangeTableEntry calls. Remove relname field from RTEs, since
it will no longer be a useful unique identifier of relations;
we want to encourage people to rely on the relation OID instead.
Further work on dumping qual expressions in EXPLAIN, too.
the parsetree representation. As yet we don't *do* anything with schema
names, just drop 'em on the floor; but you can enter schema-compatible
command syntax, and there's even a primitive CREATE SCHEMA command.
No doc updates yet, except to note that you can now extract a field
from a function-returning-row's result with (foo(...)).fieldname.
now has an RTE of its own, and references to its outputs now are Vars
referencing the JOIN RTE, rather than CASE-expressions. This allows
reverse-listing in ruleutils.c to use the correct alias easily, rather
than painfully reverse-engineering the alias namespace as it used to do.
Also, nested FULL JOINs work correctly, because the result of the inner
joins are simple Vars that the planner can cope with. This fixes a bug
reported a couple times now, notably by Tatsuo on 18-Nov-01. The alias
Vars are expanded into COALESCE expressions where needed at the very end
of planning, rather than during parsing.
Also, beginnings of support for showing plan qualifier expressions in
EXPLAIN. There are probably still cases that need work.
initdb forced due to change of stored-rule representation.
for nested typecasts. It now produces a column header of 'timestamptz'
for 'SELECT CURRENT_TIMESTAMP', rather than 'text' as it was doing for
awhile there.
Define a new function, GetCurrentTransactionStartTimeUsec() to get the time
to this precision.
Allow now() and timestamp 'now' to use this higher precision result so
we now have fractional seconds in this "constant".
Add timestamp without time zone type.
Move previous timestamp type to timestamp with time zone.
Accept another ISO variant for date/time values: yyyy-mm-ddThh:mm:ss
(note the "T" separating the day from hours information).
Remove 'current' from date/time types; convert to 'now' in input.
Separate time and timetz regression tests.
Separate timestamp and timestamptz regression test.
Given the following table:
test=# \d f
Table "f"
Column | Type | Modifiers
--------+---------+-----------
i | integer |
test | text |
If I do the following:
test=# insert into f values(1,'test');
INSERT 139549 1
test=# select i::int8,test from f;
?column? | test
----------+------
1 | test
(1 row)
It doesn't make much sense that the first column should be called
'?column?'.
The patch results in the output appearing like this:
test=# select i::int8,test from f;
i | test
---+------
1 | test
(1 row)
----------
Gavin Sherry
> > secure_ctx changes too. it will be PGC_BACKEND after '-p'.
>
> Oh, okay, I missed that part. Could we see the total state of the
> patch --- ie, a diff against current CVS, not a bunch of deltas?
> I've gotten confused about what's in and what's out.
Ok, here it is. Cleared the ctx comment too - after -p
it will be PGC_BACKEND in any case.
Marko Kreen
clause with an alias is a <subquery> and therefore hides table references
appearing within it, according to the spec. This is the same as the
preliminary patch I posted to pgsql-patches yesterday, plus some really
grotty code in ruleutils.c to reverse-list a query tree with the correct
alias name depending on context. I'd rather not have done that, but unless
we want to force another initdb for 7.1, there's no other way for now.
(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!
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.
Implement TIME WITH TIME ZONE type (timetz internal type).
Remap length() for character strings to CHAR_LENGTH() for SQL92
and to remove the ambiguity with geometric length() functions.
Keep length() for character strings for backward compatibility.
Shrink stored views by removing internal column name list from visible rte.
Implement min(), max() for time and timetz data types.
Implement conversion of TIME to INTERVAL.
Implement abs(), mod(), fac() for the int8 data type.
Rename some math functions to generic names:
round(), sqrt(), cbrt(), pow(), etc.
Rename NUMERIC power() function to pow().
Fix int2 factorial to calculate result in int4.
Enhance the Oracle compatibility function translate() to work with string
arguments (from Edwin Ramirez).
Modify pg_proc system table to remove OID holes.
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.
SQL cast constructs can be performed during expression transformation
instead of during parsing. This allows constructs like x::numeric(9,2)
and x::int2::float8 to behave as one would expect.
yet, but at least we can give a better error message:
regression=> select count(distinct f1) from int4_tbl;
ERROR: aggregate(DISTINCT ...) is not implemented yet
instead of 'parser: parse error at or near distinct'.
Tom Lane