home *** CD-ROM | disk | FTP | other *** search
- Xref: sparky comp.databases:7915 comp.databases.ingres:1921 comp.databases.informix:2452 comp.databases.oracle:2230 comp.databases.sybase:337
- Newsgroups: comp.databases,comp.databases.ingres,comp.databases.informix,comp.databases.oracle,comp.databases.sybase
- Path: sparky!uunet!charon.amdahl.com!pacbell.com!sgiblab!zaphod.mps.ohio-state.edu!saimiri.primate.wisc.edu!ames!nsisrv!stars.gsfc.nasa.gov!thompson
- From: thompson@stars.gsfc.nasa.gov (William Thompson, code 682.1, x2040)
- Subject: Connectivity between databases
- Message-ID: <17NOV199217095298@stars.gsfc.nasa.gov>
- News-Software: VAX/VMS VNEWS 1.4-b1
- Sender: usenet@nsisrv.gsfc.nasa.gov (Usenet)
- Nntp-Posting-Host: stars.gsfc.nasa.gov
- Organization: NASA/GSFC-Laboratory for Astronomy and Solar Physics
- Distribution: usa
- Date: Tue, 17 Nov 1992 21:09:00 GMT
- Lines: 51
-
- I'm currently in the market for a Unix RDBMS, and the selected software needs
- to be able to communicate with other people's databases which will probably be
- from other vendors (Oracle and Sybase for certain). I was looking for insight
- as to how this would work, and whether people had any experience of how well
- the different database products work with other SQL databases. I want to hear
- from users--I've already talked to the vendors.
-
- What we would be doing would be to compare our databases against other people's
- databases. The database would contain information about our scientific
- observations, and we would want to correlate our observations with the
- observations of other instruments--e.g. when were we pointed at the same
- target, etc. The users would *not* be storing or updating any data in the
- remote database--just looking at it. In fact, I don't really expect the user's
- to be writing to the local databases either, except for temporary tables used
- to store the results of queries.
-
- However, the database software will only represent a small fraction of the
- activities that will be going on at our site (say 5-10%), so we don't want to
- put a lot of manpower into putting together a sophisticated distributed
- database. We have also looked at transaction managers, and have decided that
- those would be inappropriate since they require that everything can be
- expressed in well-understood and predefined transactions--we want to keep a
- lot of flexibility open in the system.
-
- It seems that there are several ways to go about it:
-
- 1. The local database software could spawn a shell script which starts
- a session on the remote database which extracts the requested data
- and writes it to one or more flat ASCII files. These ASCII files
- are then imported to temporary tables in the local database and
- manipulated locally. This probably would be sufficient for our
- needs. Also, if we did this we could probably use any database
- package, since (I believe) any of them can spawn OS commands, and
- import/export ASCII text files. Does anybody have any experience
- working this way, and can comment on how well it works?
-
- 2. We could use gateway products from one vendor to another. I
- believe this requires buying additional software for at least one
- of the machines. I don't know how well these gateways work, and
- expect that the gateways from one vendor are different from those
- from another vendor. I'd be interested in hearing about people's
- experiences with gateways from Oracle, Ingres, Sybase, Informix,
- etc., and whether they think one is better than another.
-
- 3. We could use 3rd party front-ends which have their own gateways. I
- don't know much about this either--up to now I've only been
- studying the problem of the back end.
-
- Thank you in advance,
-
- Bill Thompson
-