Hi all,
I mean to create a typed hstore, called tstore for now. I'm open to
name suggestions. It'll only support a subset of core Postgres types
to begin with. Keys are always text, it's the value that's typed.
Usage is very similar to hstore; this is not a complete reference.
tstore( text, text) Creates a text key-value pair.
tstore( text, int4 ) Creates an integer key-value pair.
tstore -> text Returns a tvalue, which is basically an oid-value pair.
typeof( tvalue ) Returns the oid.
tvalue::int4 The integer value.
tvalue::text The text value.
each_int( tstore ) Set of all keys and values where the value is int4.
each_text( tstore ) Set of all keys and values where the value is text.
each( tstore ) Set of all keys and values as tvalues.
Some examples:
# select 'text: "a"'::tvalue; tvalue
----------text: "a"
(1 row)
# select 'integer: 17'::tvalue; tvalue
----------int4: 17
(1 row)
# select each_int( '"a" -> text: "b", "b" -> int: 17'::tstore );?column? | ?column?
----------+----------"b" | 17
(1 row)
#select '"a" -> text: "b", "b" -> int: 17'::tstore -> 'a'; ?column?
-----------text: "a"
(1 row)
All comments are welcome. As the project matures, I'm sure other
needed functions will crop up.
-- Johann Oskarsson http://www.2ndquadrant.com/ |[] PostgreSQL Development, 24x7 Support, Training
andServices --+-- | Blog:
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