Am 19.11.10 10:06, schrieb Frederik Ramm:
Hi,
Andreas Kalsch wrote:
One simple answer: The drivers do not work appropriately with complex SQL data types. In PHP or
node.js I will get a string that I have to parse, in MongoDB, I get a proper object or list. If I
used hstore in a consequent way (I like consequence and unification), I would have sets in sets,
It seems to me that you are mistaking "consequence" for "exaggeration". In many cases - especially
when dealing with large real-world datasets as opposed to a nice little hello-world application -,
a healthy compromise works better than grabbing one concept and trying to make the world fit that
concept.
I am sure there are some good uses for hstore, but as soon as you use it, you are waiting for
something like a document-oriented database. I ask myself: Why do I need normal columns when there
is hstore? Of course there are some answers like special indexing ... the fact: Intermingling both
concepts inside one database will make queries and schema design more complex than necessary - many,
many time-consuming choices you do not need to do in the NoSQL world. If you take a look at all
Postgres data types, you have a myriad of choices. Often, a simple design will win, especially when
you will build something more complex on top of it.
It's only one step away from switching to a document store.
Example for unnessessary complex schema design:
http://wiki.openstreetmap.org/wiki/DE:HowTo_minutely_hstore
My personal point is that my system relies on the 0.36 schema and I simply cannot change all
dependant scripts.
But just intermingling things for fun does not make the world better.
I think you're misunderstanding. hstore has not been implemented for fun. (Are you aware that
PostgreSQL can extend column indexes to hstore keys?)
Probably I am wrong ... yes I know that you can index hstore with a GIST.
MongoDB, for example, unifies worlds by simply using JSON. I don't have to manually parse things
I do not need to parse.
In turn, you will have a hard time getting the performance required for a planet-wide application
out of MongoDB.
OK, can you explain further what the bottlenecks would be?
Bye
Frederik
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