"Joe Sullivan" <Joe Sulli***@discussions.microsoft.com>

>I am trying to find the difference between two datasets.  I have tried
> merging the two datasets and then writing an xml diffgram like so:
>
>    dsA.AcceptChanges();
>    dsA.Merge(dsB, true);
>    dsA.WriteXml("D:/dev/Changes.xml", XmlWriteMode.DiffGram);
>
> It would make sense that the merge would only change the records in dsA
> that
> are different from dsB.  However, when I look at the XML file, it is
> showing
> every row as "modified" event when the previous and current values are the
> same.
>
> Am I doing something wrong here, or will it always show every row as
> modified when I execute the merge method.  Or, does someone know of a
> better
> way to show differences between two similar datasets.  I am trying to
> aviod
> parsing through every row if at all possible.
>
> Thanks,
> Joe Sullivan
> joe.sulli***@gcmweb.org
> Data Systems Administrator
> Great Commission Ministries
>
>
>

"Cor Ligthert" wrote:

> Joe,
>
> Merging from two datasets to compare should be always impossible.
> The tables that has to be merged needs the same primary key at least and
> there should not be the same key in the destiniation table as in the sending
> table.
>
> Your code makes now probably only an extra table in your dataset.
>
> A dataset is an object that holds tables objects, which hold row objects,
> which holds item objects.
>
> So that easy is it not to compare.
>
> Therefore what is it you want to compare?
>
> Cor
>
> "Joe Sullivan" <Joe Sulli***@discussions.microsoft.com>
>
> >I am trying to find the difference between two datasets.  I have tried
> > merging the two datasets and then writing an xml diffgram like so:
> >
> >    dsA.AcceptChanges();
> >    dsA.Merge(dsB, true);
> >    dsA.WriteXml("D:/dev/Changes.xml", XmlWriteMode.DiffGram);
> >
> > It would make sense that the merge would only change the records in dsA
> > that
> > are different from dsB.  However, when I look at the XML file, it is
> > showing
> > every row as "modified" event when the previous and current values are the
> > same.
> >
> > Am I doing something wrong here, or will it always show every row as
> > modified when I execute the merge method.  Or, does someone know of a
> > better
> > way to show differences between two similar datasets.  I am trying to
> > aviod
> > parsing through every row if at all possible.
> >
> > Thanks,
> > Joe Sullivan
> > joe.sulli***@gcmweb.org
> > Data Systems Administrator
> > Great Commission Ministries
> >
> >
> >
>
>
>

"Joe Sullivan" <JoeSulli***@discussions.microsoft.com>

> What I am attempting to do is update data on our live sql server that has
> been changed over time offsite and saved in an access database.  I can't
> just
> call the GetChanges() method of the dataset because I want to make sure
> that
> I get all changes across multiple runs of the application (this is an
> offline
> application that may not always be running).
>
> I am attempting to create an XML file that contains only changes to the
> data.  I figured that I could save the changes across multiple runs in the
> access database.  Then, when I am ready to synchronize with our database
> on
> the server, I could load the live data into a dataset and compare it with
> the
> dataset from the access database to just return the changed data (I cannot
> update the tables through SQL code... I have an api that I am going to run
> through the changes with).
>
> For example, say that we have changed the third column of the 1st row in
> my
> offline access system....
>
> In dsLive,
>  1, "John Doe", 100
>  2, "Jane Doe", 200
>
> in dsAccess:
>  1, "John Doe", 200
>  2, "Jane Doe", 200
>
> I want a resulitng dataset that shows the changed row:
>  current version: 1, "John Doe", 200
>  previous version: 1, "John Doe", 100
>
> Which is what I hoped to see in dsLive by calling dsLive.Merge(dsAccess).
>
> All I want to do is to update the live dataset with the access dataset and
> take advantage of versions in the dataset to compare previous and current
> versions.
>
> Thanks,
> Joe
>
> "Cor Ligthert" wrote:
>
>> Joe,
>>
>> Merging from two datasets to compare should be always impossible.
>> The tables that has to be merged needs the same primary key at least and
>> there should not be the same key in the destiniation table as in the
>> sending
>> table.
>>
>> Your code makes now probably only an extra table in your dataset.
>>
>> A dataset is an object that holds tables objects, which hold row objects,
>> which holds item objects.
>>
>> So that easy is it not to compare.
>>
>> Therefore what is it you want to compare?
>>
>> Cor
>>
>> "Joe Sullivan" <Joe Sulli***@discussions.microsoft.com>
>>
>> >I am trying to find the difference between two datasets.  I have tried
>> > merging the two datasets and then writing an xml diffgram like so:
>> >
>> >    dsA.AcceptChanges();
>> >    dsA.Merge(dsB, true);
>> >    dsA.WriteXml("D:/dev/Changes.xml", XmlWriteMode.DiffGram);
>> >
>> > It would make sense that the merge would only change the records in dsA
>> > that
>> > are different from dsB.  However, when I look at the XML file, it is
>> > showing
>> > every row as "modified" event when the previous and current values are
>> > the
>> > same.
>> >
>> > Am I doing something wrong here, or will it always show every row as
>> > modified when I execute the merge method.  Or, does someone know of a
>> > better
>> > way to show differences between two similar datasets.  I am trying to
>> > aviod
>> > parsing through every row if at all possible.
>> >
>> > Thanks,
>> > Joe Sullivan
>> > joe.sulli***@gcmweb.org
>> > Data Systems Administrator
>> > Great Commission Ministries
>> >
>> >
>> >
>>
>>
>>

"Cor Ligthert" wrote:

> Joe,
>
> I dont think that the merge will help you with that.
> http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpref/html/frlrfsystemdatadatasetclassmergetopic.asp
>
> See this row in the sample
>
>    ' Add two rows. Note that the id column can't be the
>     ' same as existing rows in the DataSet table.
>
> What you want is in my opinion a "Match and Replacerows", which I have never
> seen in ADONET.
>
> Cor
>
>
> "Joe Sullivan" <JoeSulli***@discussions.microsoft.com>
>
> > What I am attempting to do is update data on our live sql server that has
> > been changed over time offsite and saved in an access database.  I can't
> > just
> > call the GetChanges() method of the dataset because I want to make sure
> > that
> > I get all changes across multiple runs of the application (this is an
> > offline
> > application that may not always be running).
> >
> > I am attempting to create an XML file that contains only changes to the
> > data.  I figured that I could save the changes across multiple runs in the
> > access database.  Then, when I am ready to synchronize with our database
> > on
> > the server, I could load the live data into a dataset and compare it with
> > the
> > dataset from the access database to just return the changed data (I cannot
> > update the tables through SQL code... I have an api that I am going to run
> > through the changes with).
> >
> > For example, say that we have changed the third column of the 1st row in
> > my
> > offline access system....
> >
> > In dsLive,
> >  1, "John Doe", 100
> >  2, "Jane Doe", 200
> >
> > in dsAccess:
> >  1, "John Doe", 200
> >  2, "Jane Doe", 200
> >
> > I want a resulitng dataset that shows the changed row:
> >  current version: 1, "John Doe", 200
> >  previous version: 1, "John Doe", 100
> >
> > Which is what I hoped to see in dsLive by calling dsLive.Merge(dsAccess).
> >
> > All I want to do is to update the live dataset with the access dataset and
> > take advantage of versions in the dataset to compare previous and current
> > versions.
> >
> > Thanks,
> > Joe
> >
> > "Cor Ligthert" wrote:
> >
> >> Joe,
> >>
> >> Merging from two datasets to compare should be always impossible.
> >> The tables that has to be merged needs the same primary key at least and
> >> there should not be the same key in the destiniation table as in the
> >> sending
> >> table.
> >>
> >> Your code makes now probably only an extra table in your dataset.
> >>
> >> A dataset is an object that holds tables objects, which hold row objects,
> >> which holds item objects.
> >>
> >> So that easy is it not to compare.
> >>
> >> Therefore what is it you want to compare?
> >>
> >> Cor
> >>
> >> "Joe Sullivan" <Joe Sulli***@discussions.microsoft.com>
> >>
> >> >I am trying to find the difference between two datasets.  I have tried
> >> > merging the two datasets and then writing an xml diffgram like so:
> >> >
> >> >    dsA.AcceptChanges();
> >> >    dsA.Merge(dsB, true);
> >> >    dsA.WriteXml("D:/dev/Changes.xml", XmlWriteMode.DiffGram);
> >> >
> >> > It would make sense that the merge would only change the records in dsA
> >> > that
> >> > are different from dsB.  However, when I look at the XML file, it is
> >> > showing
> >> > every row as "modified" event when the previous and current values are
> >> > the
> >> > same.
> >> >
> >> > Am I doing something wrong here, or will it always show every row as
> >> > modified when I execute the merge method.  Or, does someone know of a
> >> > better
> >> > way to show differences between two similar datasets.  I am trying to
> >> > aviod
> >> > parsing through every row if at all possible.
> >> >
> >> > Thanks,
> >> > Joe Sullivan
> >> > joe.sulli***@gcmweb.org
> >> > Data Systems Administrator
> >> > Great Commission Ministries
> >> >
> >> >
> >> >
> >>
> >>
> >>
>
>
>