Client Server options

[reinaldocrespo]

Otto;

You are still missing the point. You are looking for a black cat on a dark black room. The problem is that there is no black cat. So keep searching...

Stop comparing RDP vs SQL. I use both. It is not one or the other. ADS DD gives you triggers, stored procedures, save points with roll back transactions, sql syntax, ISAM, event messaging between server and workstation, data security, zero corruption, real client-server. RDP gives you... well just that, remote desktop. See, oranges and bicycles don't compare and don't need to be pinned one against the other.

Again, you can't miss what you don't know. If the dark room feels comfortable to you, then stay there.


Reinaldo.

[lucasdebeltran]

Hi,

The ideal option would be SQLRDD, so you deliver .exe file and that accesses an SQL server.

AIS is quite slow via Internet, but SQL is not.

And in local mode you set to DBFCDX.

[reinaldocrespo]

Lucas;

If you want to compare speed of ADS vs MS-SQL via an Internet connection, then you need to compare similar technologies. If you access .dbfs via PHP using the ADS php driver, then it is every bit as fast as accessing any SQL via php. If you access DBFS via .net driver then it is every bit as fast as any SQL being accessed via the .net.

The problem here is you are trying to xbrowse a dbf over an internet connection. What makes it slow is that xbrowse wasn't designed to be fast over an internet connection. If you want to browse data over internet, then try php, pyton, or any .net such as ASP. Bear in mind that you can't even try to xbrowse any other SQL over an internet connection.

Try PHP + ADS php extension to work with your .dbfs. It is simple and FAST!

If you want to stay with win32 apps to access your .dbfs via internet, then try to avoid xbrowsing the whole dbf. Maybe browse result sets produced by SQL?


Reinaldo.

[lucasdebeltran]

Reinaldo,

Using AIS over Internet in normal dbf operations (APPEND, DELETE, LOCATE, SEEK, etc) is not as fast as TDophin and MySQL.

xBrowsing is very slow. Even creating a SQL querry and loading into an array.

But xBrowsing with TDoplphin is very fast.

So ADS should improve performance. I they do that, ADS would be the best choice and it will worth it. But not at mean time, I am afraid.

[reinaldocrespo]

Lucas;

Please share a small self contained sample using xbrowse with tdolphin over an internet connection. Perhaps you have some test data on your server that I can test? I would really like to see it working. So far I've been using php to access .dbf data over internet connections and only use AIS with FIPS encryption for data replication between servers.

You can write to me email reinaldo.crespo on gmail. Thank you.

Reinaldo.

[reinaldocrespo]

Lucas;

Perhaps you can do a test for me. Compare browsing a .dbf table using AIS from Arc32 vs. browsing a table using tdolphin over the same internet connection. Is Tdolphin using ADO?

[Rick Lipkin]

Lucas

If you are using MS Sql Server make sure you use the Local Cache option when you create your ADO recordset object. This allows your data to be cached on the client rather than thrashing over the internet.

This is only applicable to OLEDB providers that support ADO. ( sql server, oracle, db2 )

Rick Lipkin

Code: Select all

oRsUser := TOleAuto():New( "ADODB.Recordset" )
oRsUser:CursorType     := 1        // opendkeyset
oRsUser:CursorLocation := 3        // local cache
oRsUser:LockType       := 3        // lockoportunistic

cSQL := "SELECT * FROM EMPLOYEES"
TRY
   oRsUser:Open( cSQL, xCONNECT )
CATCH oErr
   MsgInfo( "Error in Opening EMPLOYEES table here" )
   RETURN(.F.)
END TRY
 

[lucasdebeltran]

Rick,

Thanks for the tip.


Reinaldo,

I use Danie´s xbrowse sample in tDolphin which goes to an ISP located in USA (sitasoft.net), while I am accessing it from Spain.

It is inmediate. Very impresive.


But accessing xBrowse with AIS in a server located in Spain but with latency over 40 ms is very very slow.

[Otto]

Reinaldo, I feel you are a little impolite in your answer to me.
Best regards,
Otto

[reinaldocrespo]

Otto;

I think you are right. I'm sorry.


Reinaldo.

[reinaldocrespo]

Lucas,

I'd like to test accessing your .dbf tables in Spain from here. Please send me the connection string (ip, port, path and name of the dd), user and passw to access the DD over AIS. Thank you.


Reinaldo.

[lucasdebeltran]

Reinaldo,

Now I set off the server.

But you can try Renee Flores sample with their server.

It is also very very slow:
http://goo.gl/gsCE8

[Otto]

Reinaldo, thank you.
Best regards,
Otto

[lucasdebeltran]

Reinaldo,

Did you try http://goo.gl/gsCE8 ?

Thanks.

[reinaldocrespo]

Lucas;

Sort of. Using arc I created a new dd connection to \\..d2g.com:2000\cursos\adsdemo\cibconwn\stc\internet.add I connect with username demo and password demo.

Once connected, the table branch on the connection repository tree will expand showing all available tables. I'm browsing table ABRPOL. It is a dbf/cdx table. It browses ok. Not too bad. However, I noticed that connection to that server (probably in Mexico) is not a fast one. Browsing a different Data Dictionary using ARC on a server in Texas is a lot faster.

I don't know ADO. Rick or Adolfo are better sources on that subject. But since ADO is tailored to work with result sets, I would think it does relatively faster xbrowsing over slow connections.

I can't see how AIS is much slower or faster. The difference between AIS and the remote server is that with AIS communication is encrypted-decrypted at both ends. What I think makes for slow xbrowsing over AIS is the connection speed itself and the fact that xbrowse is terrible with ADS RDDs, even with the Local and/or Remote servers and not just AIS. That's why I would try to test using ARC and the same connection to the same server as bench marks.

I will spend more time trying later. I will reply as soon as I have a chance. Thank you.


Reinaldo.