I beg to differ with Tom Lane's opinion, but schemas do not solve the
problem with multi-database queries because of the following reasons:
1) When dealing with large databases, the use of multiple databases
reduces the risk of wiping out all the data, and reduces the recovery
time in case of accidents.
2) Multiple databases allow for different management policies on each
database, whereas schemas require some consistency across them all.
In a heterogeneous working environment, this is a signficant issue.
3) PostgreSQL should strive for heterogeneous multi-database queries,
so that applications currently using other systems could be slowly
migrated to PostgreSQL by moving portions of a database from other
vendors to PostgreSQL. In my work, the lack of PostgreSQL - Oracle
connectivity is a disabling impediment to wider PostgreSQL usage.
--Bob
+-----------------------------+------------------------------------+
| Robert E. Bruccoleri, Ph.D. | email: bruc@acm.org |
| President, Congenomics Inc. | URL: http://www.congen.com/~bruc |
| P.O. Box 314 | Phone: 609 818 7251 |
| Pennington, NJ 08534 | |
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