Re: Index usage for tstzrange?

Josh Berkus <josh(at)agliodbs(dot)com> 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