> : Why is NUMERIC not considered numeric by TypeCategory()? Why is DATE not
> : considered a datetime type? Isn't this routine fundamentally broken?
> : If we need a category it should be taken from a pg_type field, not
> : hardwired in code...
> Thomas, what say you?
Not sure why DATE is not a date/time type. NUMERIC is not included for
two reasons: it is newer than the other code, and I'm not certain
where it should appear in a "promotion heirarchy" due to its
performance.
But in general you are right. I did the implementation using hardcoded
info, with the expectation that the eventual "right answer" would
involve allowing the type equivalence *and* type promotion info to be
stored in a table. For one thing, that is the only way afaik to get
user-defined types to participate in this implicit type coersion
scheme.
But at the time I didn't want to take the leap to defining a new table
or adding a column(s) to pg_type, until the current scheme was in the
field for a while and others had a chance to exercise it and
contribute ideas.
I was assuming that a new table would be required, rather than using
pg_type, but maybe we only need two columns in a one-to-one
relationship and if so then pg_type might suffice. Are new columns
"typecategory" and "promotiontype" sufficient??
- Thomas
--
Thomas Lockhart lockhart@alumni.caltech.edu
South Pasadena, California
