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Re: VisAD and SQL databases

Ugo Taddei wrote:
<snip>

Well, I think this is possible. Something like

rsmd.getColumnType( col_number );
(rsmd is ResultSetMetaData. The method above returns an int, which is a code - e.g. Decimal, Date, String. Anyway, I'd say it's possible, although I might be missing the right method. Any better suggestions out there?)
I used to do, for example, rs.getFloat( "my_column" );, where rs is the ResultSet. 

Just for the record, I'm not into Java programming.  ;-)
However, people are often talking about ResultSetMetaData being used to return all sorts of database structural information, including field types, foreign key references, and similar. So this bit sounds right. 

<snip>
> Bill Hibbard wrote:

But probably no
way to find out whether the set of independent variables form
a Gridded or Irregular topology (this highlights a difference
between the VisAD and SQL data models).

<snip>

Yes, that's why I think any SQL adapter will be (too much of) a trade-off.
Would it be reasonable to create a "standard practise" of having a table (i.e. visad_structure) with the relationships and datatypes (etc) of all the other elements in it?
From the point of view that creating this table and including the needed VisAD meta-data in it would let people plug in their JDBC driver, point it at the database, and then know all of these informational bits that are being mentioned here? i.e. Gridded vs Irregular topology info, etc.
Maybe it wouldn't be that hard to discuss what would be a good meta-data layout needed for such a table so that things become as automatically configuring as possible? 

:-)

Regards and best wishes,

Justin Clift



Cheers,

Ugo





--
"My grandfather once told me that there are two kinds of people: those
who work and those who take the credit. He told me to try to be in the
first group; there was less competition there."
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