Hi all,
Im trying to make a lil database server, it communicates with clients
through tcp connections.
Its pretty cool so far, but manipulating with the DataSet is messy:
There is a function which loads xml data (and schema) into the dataset but
whats the way to delete records from a dataset using xml?

So far my solution came to this:

DataSet "A" - Contains the original records
DataSet "B" - Contains same records as "A" but some have deleted

1.Create a new dataset "C" which contains deleted records using
"B.GetChanges(DataRowState.Deleted)"
2.Convert "C" into xml string and send it to the server

But ones "C" gets to server how do I delete the records in "A" using it?
I could use "foreach" on all the records in "A" and delete them if they
match records in "C", but surely theres a better way...

Thank u!
Val

Val wrote:

> Hi all,
> Im trying to make a lil database server, it communicates with clients
> through tcp connections.
> Its pretty cool so far, but manipulating with the DataSet is messy:
> There is a function which loads xml data (and schema) into the dataset but
> whats the way to delete records from a dataset using xml?
>
> So far my solution came to this:
>
> DataSet "A" - Contains the original records
> DataSet "B" - Contains same records as "A" but some have deleted
>
> 1.Create a new dataset "C" which contains deleted records using
> "B.GetChanges(DataRowState.Deleted)"
> 2.Convert "C" into xml string and send it to the server
>
> But ones "C" gets to server how do I delete the records in "A" using it?
> I could use "foreach" on all the records in "A" and delete them if they
> match records in "C", but surely theres a better way...
>
> Thank u!
> Val
>
>

Why not create a collection of objects (i.e. a collection of records to
be deleted) and pass that collection to the server? Then you could have
the server create an new instance of each record using an identifer from
each object (i.e. record). Then simply remove each object (i.e. record)
from the database. This would be easily implemented using a
persistence framework such as Gentle.Net
(http://www.mertner.com/confluence/homepage.action).

This is pretty much the same basic idea, only it is much more OO than
just using ADO/ADO.NET, easier to implement IMHO, and it would possibly
be much faster.

Shock

Thanks Shock,
I thought it would be better to have a dataset with all the records from the
db in memory, and manipulate the records inside the dataset. Then have a
thread that synchronizes the dataset with db every once in a while.

This server will be accessed by multiple users at once, and if all of them
delete records - the server will have to clear the dataset and refill it
from db every time a record is deleted. If the table contains alot of
records this might be pretty laggy.

This whole thing is in C# btw.
I don't know maybe im just being strange here, ne way I hope someone out
there can clarify this whole thing.

Thanks again,
Val

"Shock" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)...
> Val wrote:
>
>> Hi all,
>> Im trying to make a lil database server, it communicates with clients
>> through tcp connections.
>> Its pretty cool so far, but manipulating with the DataSet is messy:
>> There is a function which loads xml data (and schema) into the dataset
>> but whats the way to delete records from a dataset using xml?
>>
>> So far my solution came to this:
>>
>> DataSet "A" - Contains the original records
>> DataSet "B" - Contains same records as "A" but some have deleted
>>
>> 1.Create a new dataset "C" which contains deleted records using
>> "B.GetChanges(DataRowState.Deleted)"
>> 2.Convert "C" into xml string and send it to the server
>>
>> But ones "C" gets to server how do I delete the records in "A" using it?
>> I could use "foreach" on all the records in "A" and delete them if they
>> match records in "C", but surely theres a better way...
>>
>> Thank u!
>> Val
>
> Why not create a collection of objects (i.e. a collection of records to be
> deleted) and pass that collection to the server? Then you could have the
> server create an new instance of each record using an identifer from each
> object (i.e. record). Then simply remove each object (i.e. record) from
> the database. This would be easily implemented using a persistence
> framework such as Gentle.Net
> (http://www.mertner.com/confluence/homepage.action).
>
> This is pretty much the same basic idea, only it is much more OO than just
> using ADO/ADO.NET, easier to implement IMHO, and it would possibly be much
> faster.
>
> Shock