Hi
I am trying to program a VB.Net Windows application (in a client server
environment with multiple users) and am seeking some help about a
possible technique to handle concurreny issues. I am using ADO.Net,
typed datasets, and data binding through code. Is there any way that
when a user pulls out a record (and this user could only pull one
record at a time) into his local dataset, that a flag can be sent back
to the server for that record, which will then in turn give a message
to any other user that "this file is being modified by another user"
and then allow them to view the record but make it read-only? I'm
thinking this could prevent any "after the fact" concurrency issues.
At the same time though, I realize it is only the user who pulls the
record who's machine knows that the record is being modified. Could I
perhaps write to another table a key field that the other computers
check? ....or maybe insert (the flag), then do a select again (but
this seems like a lot of unnecessary processing)...a ny thought on how
one might pull off such a system?
Thanks so much for any help!
3  1743 
VanVee,
Have a look at optimistic an pesimistic concurrency. Because ADONET is
disconnected is pesimistic concurrency as you describe here (classic name
recordlocking) not easy to do.
You can have a look at these pages about this. http://msdn.microsoft.com/library/de...cyChecking.asp
I hope this helps?
Cor
<va****@comcast .net> Hi
I am trying to program a VB.Net Windows application (in a client server
environment with multiple users) and am seeking some help about a
possible technique to handle concurreny issues. I am using ADO.Net,
typed datasets, and data binding through code. Is there any way that
when a user pulls out a record (and this user could only pull one
record at a time) into his local dataset, that a flag can be sent back
to the server for that record, which will then in turn give a message
to any other user that "this file is being modified by another user"
and then allow them to view the record but make it read-only? I'm
thinking this could prevent any "after the fact" concurrency issues.
At the same time though, I realize it is only the user who pulls the
record who's machine knows that the record is being modified. Could I
perhaps write to another table a key field that the other computers
check? ....or maybe insert (the flag), then do a select again (but
this seems like a lot of unnecessary processing)...a ny thought on how
one might pull off such a system?
Thanks so much for any help!
Thank you Cor! You have been so helpful! How much do I owe you?
Cor Ligthert wrote: VanVee,
Have a look at optimistic an pesimistic concurrency. Because ADONET
is disconnected is pesimistic concurrency as you describe here (classic
name recordlocking) not easy to do.
You can have a look at these pages about this.
http://msdn.microsoft.com/library/de...cyChecking.asp
I hope this helps?
Cor
<va****@comcast .net>
Hi
I am trying to program a VB.Net Windows application (in a client
server environment with multiple users) and am seeking some help about a
possible technique to handle concurreny issues. I am using
ADO.Net, typed datasets, and data binding through code. Is there any way
that when a user pulls out a record (and this user could only pull one
record at a time) into his local dataset, that a flag can be sent
back to the server for that record, which will then in turn give a
message to any other user that "this file is being modified by another
user" and then allow them to view the record but make it read-only? I'm
thinking this could prevent any "after the fact" concurrency
issues. At the same time though, I realize it is only the user who pulls
the record who's machine knows that the record is being modified.
Could I perhaps write to another table a key field that the other computers
check? ....or maybe insert (the flag), then do a select again (but
this seems like a lot of unnecessary processing)...a ny thought on
how one might pull off such a system?
Thanks so much for any help! Thank you Cor! You have been so helpful! How much do I owe you?
Nothing more than these words.
HTH
Cor This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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