new version of high level language

[Clive Page]

On Thu, 27 Feb 2003, Reagan Moore wrote:

> We have the technology to map from an XML specification of
> attributes, values, and operations on values, to the SQL required by
> a particular database (Oracle, DB2, Sybase, SQLServer, PostgresSQL,
> Informix).

> The technology does require the registration of the table structure,
> foreign keys, and schema of each database for the automation of the
> SQL generation.

> Are there other types of databases in current use?

That depends what you mean by "types".  Quite a number of well-used
astronomical data archives don't rely on commercial or even free RDBMS,
they use an astronomer-written DBMS.  The LEDAS facility here, for example
(ledas-www.star.le.ac.uk) now supports searching of USNO-B1.0 - but this
isn't loaded into any DBMS, but uses the WCSTOOLS software written at CfA
which access the USNO-B data files in their distribution format, and
unpacks them on the fly.   Seems efficient enough to me for simple cone
searches (we don't yet support cross-matching with other catalogues).
Other places do something similar: when I asked Francois Ochsenbein if he
had managed to ingest the whole of USNO-B1.0 (over a billion rows) into
Sybase he told me that it was too large and he hadn't even attempted it.
I don't know how Vizier serves it up (maybe Francois can tell us) but I
expect CDS wrote the software in-house.  So these systems don't speak SQL
at all.

There are also one or two facilities using object-oriented DBMS - we use
O2 here for our internal XMM-Newton operations, and are about to make its
interface public.  This speaks OQL - semi-standarized, but not the
same as SQL.

By the way, you left MySQL of your list of RDBMS - perhaps the most
widely used one in astronomy?

-- 
Clive Page,
Dept of Physics & Astronomy,
University of Leicester,    Tel +44 116 252 3551
Leicester, LE1 7RH,  U.K.   Fax +44 116 252 3311