Re: access as/400 database files w/Visual Basic 6 -- MIDRANGE-L



>>Sockets could be tough, I think. The details of the sockets interface to
host servers are not generally available - I think you need to be a part of
PartnerWorld to get LIPIs (Licensed Internal Product Interfaces?) Of
course, you could write your own server.

     There is no reason to write this interface. Many iSeries developers,
CMI included, have packages available. I think ANSA was posted earlier as
having a solution. The Sockets interface may be more difficult to install
but the advantages are worth the extra effort.

     Our web server uses IIS and VBScript to launch a COM object. The
methods within this object completely hide the Socket interface and the
impact on RPG programs can be held to a minimum without API calls. The
overview of the process is described here...
http://www.cm-inc.com/WhatsNew/UsingIIS.htm

     We have a complete demonstration site from our home page. The Socket
interface isn't the only technique available, along with the program to
program calls, we have a few flavors of iSeries spoolfile support. One of
the most recent examples we've done also uses the Socket interface... It
processes XML for our new Macromedia FlashMX applications.

     If you need a Socket interface and want more details, let me know
privately. Even if you still think it's to hard to obtain or develop.

Ken Slaugh  (707) 795-1512 x118
Chouinard & Myhre, Inc.
AS/400 Professional Administrator/MSE
Client Access Specialist
http://www.cm-inc.com/



                    Vernon Hamberg
                    <vhamberg@attbi.com        To:     midrange-l@midrange.com
                    >                          cc:
                    Sent by:                   Subject:     Re: access as/400 
database
                    midrange-l-admin@mi        files w/Visual Basic 6
                    drange.com


                    08/12/2002 09:04 PM
                    Please respond to
                    midrange-l






I'll throw my hat in the ring here. I've used a couple of these.

RDO (you didn't list this) is a layer on top of ODBC that avoids the jet
engine of VB. Jet is about the worst option, as it goes to the least common
denominator. Take a look at the Client Access ODBC Drive manual from a few
releases ago - is it available in more recent release? It's excellent.

ADO is a thin layer on top of OLE/DB, for ease of use.

You could write to both APIs and get a little better performance
(difference greater with RDO vs. ODBC)

NetServer is for entire files only - no record-level access.

Performance with ODBC and OLE/DB is completely dependent on good use of
indexes, so turn on STRDBG in the serving job QZDASOINIT. V5R1 version of
ODBC driver lets you turn this on from the data source definition. Then you
can get index recommendations. You CAN get excellent response from ODBC
with good indexes and larger block sizes, etc. Likewise with OLE/DB. Check
the Knowledge Base.

Someone suggested stored procedures. Excellent approach - let the hard
database work take place on the server, then deliver only what is
absolutely needed.

Sockets could be tough, I think. The details of the sockets interface to
host servers are not generally available - I think you need to be a part of
PartnerWorld to get LIPIs (Licensed Internal Product Interfaces?) Of
course, you could write your own server.

Take a look at Visual Age for RPG - IBM's product - it creates Windows apps
with 'native' record-level data access. It can also generate Java from RPG
code. It comes in Websphere Development Studio Client (newer) or Websphere
Development Tools (older)

Net.data may be an option, too, but only for web pages.

At 03:15 PM 8/12/02 -0500, you wrote:
>I'm not sure how I will access the iSeries data.  I know that ODBC is
>probably the least efficient of all approaches, but it is also the common
>denominator for access to many databases.
>
>I would like to see reasons for & against the use of each of these
>approaches (ADO, ODBC,OLE/DB, Sockets, NetServer) to access the database.
>
>I am doing some research on how to access the iSeries data directly from a
>VB
>application (sales order entry front-end).
>
>The VB application uses a SQL server 2000 database for its local tables,
and
>constructs XML to send/receive data with an EAI application that passes
data
>back and forth to the iSeries.  It does not currently have any direct
access
>to the iSeries database.
>
>We are looking at various methods of retrieving iSeries data directly for
>display/update.  I'm currently evaluating the DataGate/400 software from
>ASNA, which uses sockets to communicate with the iSeries.
>
>I'm also evaluating the use of ASNA's AVR (Visual RPG) product to build
this
>sub-application instead of having to build the functionality in the VB
>application (OR, heaven forbid, using a screen-scraping application like
>JWALK).

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