On 21.03.2013 06:07, Vasilis Ventirozos wrote:
On Thu, Mar 21, 2013 at 5:58 AM, Tom Lane<tgl@xxxxxxxxxxxxx> wrote:
What I find more disturbing is that this is what I get from the example
in HEAD:
regression=# explain SELECT * FROM a WHERE ts<@
tstzrange('2013-01-01','2013-01-01 00:10:00');
ERROR: XX000: type 1184 is not a range type
LOCATION: range_get_typcache, rangetypes.c:1451
Haven't traced through it to determine exactly what's happening, but
isn't this a legitimate usage? And if it isn't, surely a more
user-facing error ought to be getting thrown somewhere upstream of here.
It is a legit usage, this is from a test i did myself (9.2.3)
test=# explain SELECT * FROM a WHERE ts<@
tstzrange('2013-01-01','2013-04-01 00:10:00');
QUERY PLAN
------------------------------------------------------------------------------------
Seq Scan on a (cost=0.00..23.75 rows=1 width=44)
Filter: (ts<@ '["2013-01-01 00:00:00+02","2013-04-01
00:10:00+03")'::tstzrange)
Looks like the range type cost estimation patch broke this, back in
August already. The case of var <@ constant, where constant is a range
and var is an element, that's broken. The cost estimation function,
rangesel(), incorrectly assumes that the 'var' is always a range type.
It's a bit worrying that no-one noticed until now. I'll add a test for
that operator to the rangetypes regression test.
The immediate fix is attached, but this made me realize that rangesel()
is still missing estimation for the "element <@ range" operator. It
shouldn't be hard to implement, I'm pretty sure we have all the
statistics we need for that.
- Heikki
diff --git a/src/backend/utils/adt/rangetypes_selfuncs.c b/src/backend/utils/adt/rangetypes_selfuncs.c
index 76dc913..c450c6a 100644
--- a/src/backend/utils/adt/rangetypes_selfuncs.c
+++ b/src/backend/utils/adt/rangetypes_selfuncs.c
@@ -154,8 +154,6 @@ rangesel(PG_FUNCTION_ARGS)
}
}
- typcache = range_get_typcache(fcinfo, vardata.vartype);
-
/*
* OK, there's a Var and a Const we're dealing with here. We need the
* Const to be of same range type as the column, else we can't do anything
@@ -169,6 +167,8 @@ rangesel(PG_FUNCTION_ARGS)
*/
if (operator == OID_RANGE_CONTAINS_ELEM_OP)
{
+ typcache = range_get_typcache(fcinfo, vardata.vartype);
+
if (((Const *) other)->consttype == typcache->rngelemtype->type_id)
{
RangeBound lower, upper;
@@ -185,6 +185,8 @@ rangesel(PG_FUNCTION_ARGS)
}
else
{
+ typcache = range_get_typcache(fcinfo, ((Const *) other)->consttype);
+
if (((Const *) other)->consttype == vardata.vartype)
constrange = DatumGetRangeType(((Const *) other)->constvalue);
}
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