SQL to FLEX over the Internet

[Dustin69]

Hi all



I'm looking for some advice on the technologies I should be
looking at for getting data from SQL Server 2008 into my Adobe Air
application. I'm not a programmer by trade but do have some
experience in VB, C# and now Actionscript/MXML & .NET. I'm
getting on really well so far with Flex Builder but have reached
the stage where I need to grab data from a SQL box over the
Internet. I've had limited success with WSDL, being able to return
single variables but encountering a known Flex bug when trying to
generate the classes required for pulling in .NET data tables or
datasets. Based on the following criteria, can anyone point me at
the technologies/areas I should be looking at?



1. Back end server - currently a single Windows Server 2008
Standard with SQL 2008 Standard and IIS. Intention is to separate
and provide redunancy by using a clustered pair of SQL boxes and
separate IIS servers to host the SOAP services.

2. Client - running Adobe Air, will need to authenticate
using a locally stored username and password. The authenticating
server should also perform checks on client IP address.

3. All communication between client and server should be
secure.

4. On first connection to the server, the client will be
required to read in around 10 small tables, the largest of which
having up to around 500 rows of String variables (i.e. no large
image/binary data to worry about)

5. Thereafter, the client will need to check-in for updates
as frequently as possible - at least once every 15 seconds. Updates
would often be 0-10 rows and never more than 200.

6. Potential to scale up to around 2000 clients.



If you have any questions please ask away. From what I've
read so far, WSDL might be slow and inappropriate. I've seen
Enterprise Services mentioned but not really sure what that is yet.
Must do some more reading.



Any help and direction, URLs for further reading etc. greatly
appreciated.



Thanks in advance, Dustin.

[ChrisKStuart · Accepted solution]

Consider encoding data into AMF format before sending to
client. This benchmark compares many data communication approaches,
best performance was achieved with AMF (Select "Flex AMF - 5000
Rows" from dropdown):


http://www.jamesward.com/census/


"The Flex AMF benchmark makes a RemoteObject request to the
server for 5000 rows. The server serializes the data in the AMF
format. AMF is a binary object format for ActionScript objects in
the Flash Virtual Machine. The client gets the AMF data over HTTP,
shoves it into memory, then updates the DataGrid with the 5000
rows. The DataGrid supports client side sorting.



Results:

Out of all the benchmarks AMF is by far the fastest and
smallest across the wire. There is nearly no parse time because the
objects are already AS objects (instead of XML or another text
based object representation). Render time is also extremely fast
due to Flash's, Mozilla Tamarin JIT'd VM. If you try sorting you
will again see the performance of the VM. Notice that sorting is
faster in the AMF benchmark than in the E4X benchmark because the
objects are typed AS objects rather than XML objects."



This post contains AMF benefits and example code:


http://flex.sys-con.com/node/468744

[Dustin69]

Thanks Chris, am learning fast here. Currently playing with
WebORB which looks like the kind of thing I might be after. Any
other recommendations welcome.