TomohitoNakayama wrote: > Hello. > > I think this is a question , which may raise up document and code issue. > //Reading spec of DRDA at opengroup (http://www.opengroup.org/) is > best shortcut ?
I've never heard that specification described as a shortcut #:), but yes that is the protocol that is used. As for your question about the difference between EmbedConnection and Networked Connection ... The Networked Connection is really just a remote handle to an EmbedConnection. The network client JDBC driver translates JDBC calls into protocol sent over TCP/IP and then Network Server translates that protocol back into JDBC calls to the Embedded driver. The whole system is a JDBC -> protocol -> JDBC converter. So for every client connection there is a corresponding EmbedConnection doing the real work. Sometimes the JDBC on the server side is not exactly the client JDBC call but some equivalent, for example, DriverManager.getConnection() will become Driver.connect() within network server. Sometimes also network server uses Derby internal intefaces where a straight JDBC call is not available, but generally try to avoid it. Some places to do more reading. Some general info on network server in the user guide at http://db.apache.org/derby/docs/10.1/adminguide/cadminov825266.html The client functional spec http://db.apache.org/derby/papers/DerbyClientSpec.html The protocol specs http://www.opengroup.org/dbiop In Volume 1 take a look at Figure 4-2 Establishing a Connection to a Remote Database Manager This shows the protocol flow for creating a connection. You can find definitions of specific DDM objects referenced there, e.g. ACCRDB, in the DDM manual (Volume 3). I think the figures in Chapter 4 of volume 1 are a good place to get a general idea of the protocol flow without having to do a lot of translation. Sorry, don't know of anyone who has tried to translate this spec into Japanese #:) I hope I understood the question correctly. Can you close out DERBY-458 and file the code or doc issue if it arises. Thanks Kathey
