Another hstore_type idea
Hello,
after reading the thread on "Typed hstore proposal", I wonder if another
minded extension of hstore would be benefical:
add additional hstore types with numerical data type for the values.
e.g.: hstore_float : text -> float
This should allow to add some nice aggregation function on these hstore,
e.g.
select distinct_sum(x) from
(
a -> 1 b -> 5
a -> 3 c -> 2
)
=>
a -> 4 b -> 5 c -> 2
I have a small case where I'm doing this with a custom type (text,
float) , but with poor performances.
I guess that such an extension would make sense if it were to bring a
significant performance gain compared to the custom type approach.
best regards and Merry Christmas,
Marc Mamin
On Fri, Dec 23, 2011 at 7:06 AM, Marc Mamin <M.Mamin@intershop.de> wrote:
after reading the thread on "Typed hstore proposal", I wonder if another
minded extension of hstore would be benefical:add additional hstore types with numerical data type for the values.
I would expect the primary *performance* value in an "hstore
extension" to come from things that allow accessing data without
needing to "unbox" it.
(I remember the concept of unboxing from APL; it seems to have been
subsumed by object oriented terminology...
http://en.wikipedia.org/wiki/Object_type_%28object-oriented_programming%29#Unboxing)
The big "win" comes not as much from type matching (which seems to me
like a morass, as you'll need the zillion Postgres types to cover all
the cases) as it comes from avoiding the need to take the "blobs" of
tuple data and re-parse them.
--
When confronted by a difficult problem, solve it by reducing it to the
question, "How would the Lone Ranger handle this?"