On Thu, Mar 21, 2013 at 5:58 AM, Tom Lane <tgl@xxxxxxxxxxxxx> wrote:
Josh Berkus <josh@xxxxxxxxxxxx> writes:
> I just noticed that if I use a tstzrange for convenience, a standard
> btree index on a timestamp won't get used for it. Example:
> table a (
> id int,
> val text,
> ts timestamptz
> );
> index a_ts on a(ts);
> SELECT * FROM a WHERE ts <@ tstzrange('2013-01-01','2013-01-01 00:10:00')
> ... will NOT use the index a_ts.
Well, no. <@ is not a btree-indexable operator.
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.
regards, tom lane
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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)
