RE: ODBC FROM iSeries - huh?

["Joe Pluta" <joepluta@xxxxxxxxxxxxxxxxx>]

> From: John Taylor
>
> The CLI is not a communications protocol; it's just a database API.

I was looking at the CLI, and I saw a 10-character server name, which seemed
to me to be no more than enough to point to some table with the appropriate
communications information.  Evidently this is the RDBDIRE table.  One of
the entry types for the RDBDIRE allows you to specify an ARDPGM to handle
the requests.  I suspect this would ne the first step down the slippery
slope to roll-your-own client/server communications.


> You don't really need a generic driver. You see, ODBC and CLI are
> virtually
> equivalent in terms of syntax, and semantics. The SQL CLI is a standard
> created by the X/Open Standards Group. ODBC is MS's implementation of that
> standard. Of course, they've "embraced and extended" it, but they remain
> very similar.
>
> The big trick is how to get the two machines communicating.

So what this means is that, in addition to having a CLI-capable SQL engine,
you must also support a standard communication API, right?  How do I know
which comms APIs a given SQL engine supports?  Or is that yet another piece
that I have to download and install?

And in the case of, say, an ODBC request from Windows to Oracle running on a
Linux machine: How do I tell the ODBC wrapper on Windows the location of the
database on the Linux machine?  How do I tell the ODBC wrapper what comms
protocol is being used?  Or is there a default comms protocol that ODBC
uses?

Wow, every time I peel a layer off this onion, I cry harder <grin>...


> Personally, I don't see why anyone would bother. The conventional argument
> is that they wish to read/update a remote database directly
> through RPG, but
> I wonder if they aren't thinking in terms of doing a simple
> READ/CHAIN et al
> against Oracle. Because that's not the way it works.

No doubt - CLI is way different than native I/O.


> Call me crazy, but I'd much rather just use JDBC.

How does JDBC simplify this mess?  Because the JDBC type 3 driver sends the
request from machine to machine in a platform-independent way, thus allowing
the CLI request from the source machine to be directly executed on the
target machine?

Joe