I feel compelled to point out a problem with this system. I
originally used the counter table functionality for all of my
projects but have completely dropped it now. The problem
that I had was that occasionally there would be a database
glitch that would leave a counter in a locked state. This
happened regularly with MS Access (I know), but it would
also happen with MS SQL Server, which I thought would be
safe. Each time it happened it would mess things up until
it was reset. I found that it is much safer to use an autoincrementing
identity field and then look up the value, either using transactions
or with userreference stored in the table. My 2 cents.

Stefan

At 07:53 AM 5/22/2002 -0400, you wrote:
>One of the beauties about the method that was written for the storefront is
>that if a particular table does not have a counter created for it, it will
>create one automatically. The counter table has three fields: counter_name
>(varchar 35 characters), counter_value (integer), and locked (integer).
>
>The calling tag is:
>
><@ASSIGN local$NewID "<@CALLMETHOD scope$variable 'GetNextID(xxx)'>">
>
>where 'scope' and 'variable' are what you've declared your object instance
>to be and 'xxx' is the name of the counter you wish to call. I use the table
>name for the name of the counter to keep things easy to remember. To use the
>value brought back by the call to the counter, use <@VAR NewID SCOPE=Local>.
>For your situation you could have this:
>
><@ASSIGN local$NewCourseID "<@CALLMETHOD scope$variable
>'GetNextID(course)'>">
><@ASSIGN local$NewCourse_CrosslinkID "<@CALLMETHOD scope$variable
>'GetNextID(course_crosslink)'>">
>
>in a results action immediately before the insert for the course table. You
>would then have two variables:
>
><@VAR NewCourseID SCOPE=Local>
>
>would contain the courseID and:
>
><@VAR NewCourse_CrosslinkID SCOPE=Local>
>
>would contain the course_crosslinkID.
>
>Hope this helps,
>
>Steve Smith
>
>Skadt Information Solutions
>Office: (519) 624-4388
>GTA:    (416) 606-3885
>Fax:    (519) 624-3353
>Cell:   (416) 606-3885
>Email:  [EMAIL PROTECTED]
>Web:    http://www.skadt.com
>
>
>-----Original Message-----
>From: [EMAIL PROTECTED]
>[mailto:[EMAIL PROTECTED]]On Behalf Of Dan Stein
>Sent: May 21, 2002 2:34 PM
>To: Multiple recipients of list witango-talk
>Subject: Re: Witango-Talk: Next WiTango_SQL conundrum
>
>
>The first suggestion sounds interesting can you expand?
>Is the counter table pre populated how do I do GetNextID method?
>I'll try and dig up the demo.
>
>Dan
>
>on 5/21/02 1:28 PM, Steve Smith at [EMAIL PROTECTED] wrote:
>
> > Two suggestions. First, why not go with a counter table and use the
> > GetNextID method that was included in the TCF for the storefront demo. It
> > retrieves the next id which you can then use in your insert for the course
> > table AND for the course_crosslink table. It will guarentee that you have
> > the right value in both.
> >
> > The other suggestion if you are determined to not use a counter table is
>to
> > use the same values for the insert in your search rather than searching
>for
> > max course_ID. You run a far less chance of obtaining the wrong course_ID
>if
> > use the exact same <@ARG xxx> values for the search criteria that were
>used
> > in the insert action.
> >
> > Hope this helps,
> >
> > Steve Smith
> >
> > Skadt Information Solutions
> > Office: (519) 624-4388
> > GTA:    (416) 606-3885
> > Fax:    (519) 624-3353
> > Cell:   (416) 606-3885
> > Email:  [EMAIL PROTECTED]
> > Web:    http://www.skadt.com
> >
> >
> > -----Original Message-----
> > From: [EMAIL PROTECTED]
> > [mailto:[EMAIL PROTECTED]]On Behalf Of Dan Stein
> > Sent: May 21, 2002 11:58 AM
> > To: Multiple recipients of list witango-talk
> > Subject: Witango-Talk: Next WiTango_SQL conundrum
> >
> >
> > OK I have fixed everything else data is where it needs to be and everyone
> > was a big help.
> >
> > Here is my next issue.
> >
> > When I create a course with create_course.taf after the insert there is a
> > DBMS that gets Max course_ID and set's it to a local variable.
> >
> > That is because I need to know what the course_ID that was assigned by SQL
> > to the inserted course.  I then use this to insert into the
>course_crosslink
> > table the course_ID and some other values.
> >
> > It looks like sometimes it failed to set the correct course ID I guess
>there
> > was some fast enough data entry going on from more than one person so the
> > Max did not get the right number. At least it is the only thing I can
>think
> > of that would cause the missing course_ID's in course_crosslink. Since the
> > insert action comes right the DBMS I can see how it could fail without an
> > error message to the user which I think I would have heard about.
> >
> > I know there is some way to lock the table or someway to make sure I
> > retrieve the correct value but I don't know how to write it in WiTango or
>as
> > a DBMS.
> >
> >
> >
> > --
> > Dan Stein
> > Digital Software Solutions
> > 799 Evergreen Circle
> > Telford PA 18969
> > 215-799-0192
> > 610-256-2843
> > Fax 413-410-9682
> > FMP,Tango, EDI,SQL 7
> > [EMAIL PROTECTED]
> > www.dss-db.com
> >
> >
> > ________________________________________________________________________
> > TO UNSUBSCRIBE: send a plain text/US ASCII email to [EMAIL PROTECTED]
> >               with unsubscribe witango-talk in the message body
> >
> > ________________________________________________________________________
> > TO UNSUBSCRIBE: send a plain text/US ASCII email to [EMAIL PROTECTED]
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> >
>
>--
>Dan Stein
>Digital Software Solutions
>799 Evergreen Circle
>Telford PA 18969
>215-799-0192
>610-256-2843
>Fax 413-410-9682
>FMP,Tango, EDI,SQL 7
>[EMAIL PROTECTED]
>www.dss-db.com
>
>
>________________________________________________________________________
>TO UNSUBSCRIBE: send a plain text/US ASCII email to [EMAIL PROTECTED]
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>
>________________________________________________________________________
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