RDA or Replication
chamal kalamulla
I am developing my first pocket app. i read about RDa and also replication
on books online. and then i though RDa is the best suitability for my
application. then i read one of the entreies in this news group. which
confused me.
as i under stand to do RDA
1 i dont need to have have bussiness logic in local sql CE as when doing RDA
the bussiness logic in SQL will be propogated to the local DB. ?
2.when doing RDA the table which the RDA is performed must not exist in the
SQLCE DB.?
rda.Pull("UserList","Select Title,FirstName from
UserList",rdaOleDbConnectString, RdaTrackOption.TrackingOnWithIndexes,"ErrorTable");
Ie the Userlist table must not exist on the SQL CE DB
3. If the case is as above where i need to delete each time the userlist
before doign the RDA. i do have big probelem in hand. some table need to
remain on the local
4. when doing a RDA push will i have to delete the table on the SQL CE DB?
5.Can i write the data to the local SQL CE and the slq DB at the same time
disegarding writting failuiers in writing to the SQL.will it create
duplication issues.? i will cause duplication issues when using RDA Push.
thanks in advance
chamal
P.S I have added the news group question and answer which confused me below
********************************************
well, you can try to execute a query against the table and catch the
exception that it's not there -or- you can look at the Information Schema
Views included in SQL CE to determine if the table is there by name.
The TABLES view in INFORMATION_SCHEMA will give you a list
of tables currently in your database.
Try: SELECT * FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = '{your table name}'
--
Darren Shaffer
..NET Compact Framework MVP
Principal Architect
Connected Innovation
www.connectedinnovation.com
"Philip Germanos" <PhilipG...@discussions.microsoft.com> wrote in
message news:38A4F1FE-BDE5-412B...@microsoft.com...
> Ok, then suppose i have an sqlCe db but i dont know if it contains table
> X,
> and i want to pull data into table X, prior to doing the pull how can i
> test
> the db to see if table X exists or no?
>
> Thank you.
>
> "Darren Shaffer" wrote:
>
>> the table must not exist locally when you execute your RDA Pull.
>> it is up to you to delete it prior to doing the Pull.
>> --
>> Darren Shaffer
>> ..NET Compact Framework MVP
>> Principal Architect
>> Connected Innovation
>> www.connectedinnovation.com
>>
>> "Philip Germanos" <PhilipG...@discussions.microsoft.com> wrote in
>> message news:B64AA99D-AB12-4560...@microsoft.com...
>> > Hello,
>> >
>> > When using RDA, if the table selected to receive the data exists
>> > already,
>> > does RDA automatically deletes it, or i have to delete it manually?
>> >
>> > thank you
>>
>>
>>
2.
Arun
>I am developing my first pocket app. i read about RDa and also replication
>on books online. and then i though RDa is the best suitability for my
>application. then i read one of the entreies in this news group. which
>confused me. as i under stand to do RDA
Answering your question, you have not specified the volume of data
to be synchronized here. The best way is to keep one subscription
for the database and merge replicate with all the devices
Trust me, you can go with Merge Replication if the data can get
modified at both ends (PC & PPC).
Remember one more important aspect while choosing between sync
techniques, you don't have control in merge replication type of
synchronization.
Consider a scenario, where you need to keep the record data that is
altered at the desktop and not the worker's. But when merge
replicating there might be a chance of loosing desktop record
instead will be overwritten by worker's record. Considering this and
if you are more concerned about the database size and the teedious
merge replication setting, you can opt RDA and the merge functionality
you need to
handle programmatically, you need to design the database in such a
way to identify the records modified with datetime stamp and the
type of change (ADD/MODIFIED/DELETED).
>1 i dont need to have have bussiness logic in local sql CE as when doing RDA
>the bussiness logic in SQL will be propogated to the local DB. ?
SQL Server CE RDA Pros:
1. Simple to setup
2. Rich functionality provided by SQL Server CE
SQL Server CE RDA Cons:
1. SQL Server CE takes up memory
2. No merging functionality built-in (we will have to implement it)
SQL Server CE Merge Replication Pros:
1. Tedious setup
2. Merging functionality built-in
3. Rich functionality provided by SQL Server CE
SQL Server CE Merge Replication Cons:
1. SQL Server CE takes up memory
2. Merging functionality built-in (You cannot handle)
>2.when doing RDA the table which the RDA is performed must not exist in the
>SQLCE DB.?
>rda.Pull("UserList","Select Title,FirstName from
>UserList",rdaOleDbConnectString, RdaTrackOption.TrackingOnWithIndexes,"ErrorTable");
>Ie the Userlist table must not exist on the SQL CE DB
Yes you have to delete the table before pulling
That's where you have to use (Darren Shaffer's post)
INFORMATION_SCHEMA.TABLES to check if the table already exists or not
SELECT * FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_NAME = '{your table name}'
>3. If the case is as above where i need to delete each time the userlist
>before doign the RDA. i do have big probelem in hand. some table need to
>remain on the local
Use temporary tables and pul only the updated records to SQL CE and
loop through and insert it to the main tables.
Drop the temp tables once it is done.
>4. when doing a RDA push will i have to delete the table on the SQL CE DB?
Yes, it is must
>5.Can i write the data to the local SQL CE and the slq DB at the same time
>disegarding writting failuiers in writing to the SQL.will it create
>duplication issues.? i will cause duplication issues when using RDA Push.
You have to handle the merge functionality in RDA, that is the
advantage you have in RDA than Merge Replication.
Hope this helps,
Cheers,
Arun.
www.innasite.com
Darren Shaffer
I have a detailed decision flowchart and a pros/cons matrix comparing
merge, rda, and web services. The webcast is available on-demand at:
http://msevents.microsoft.com/cui/WebCastEventDetails.aspx?EventID=1032268682&EventCategory=5&culture=en-US&CountryCode=US
--
Darren Shaffer
.NET Compact Framework MVP
Principal Architect
Connected Innovation
www.connectedinnovation.com
"chamal kalamulla" <chamalk...@discussions.microsoft.com> wrote in
message news:1AB5C4D6-0A09-418B...@microsoft.com...