SQL database & ODBC is wrong path for high-perf RT. ODBC is rather slow as it was never designed by Microsoft to be used as a real-time streaming tool. Also all standard SQL databases are way too slow for real time applications.
Only proprietary binary low-level dbs like AmiBroker own, that are very low level and not SQL based are able to offer right speed. As for interfaces - only direct APIs (like AmiBroker Dev Kit) that operate directly on binary data via direct pointers and no need for copying data and without SQL overhead are fast enough. For commercial databases that offer better performance than SQL see Berkeley DB http://www.oracle.com/database/berkeley-db/db/index.html (Read their white papers that explain why all relational, sql-based databases are simply too slow) Best regards, Tomasz Janeczko amibroker.com ----- Original Message ----- From: "lucianomt" <[email protected]> To: <[email protected]> Sent: Monday, May 18, 2009 6:30 PM Subject: [amibroker] ODBC + DDE >I am trying to set up real-time feeds on AB. I have a SQL database that >contains all the necessary data. The only problem is the >very high delay I get using the ODBC plug-in. To pull up about 1000 bars for >150 tickers takes approx. 10 minutes, which makes it >impractical for real-time. (The same process using local database takes 1 >second.) > > So my first question is: am I doing something wrong? Is there any way to > improve this performance significantly or is the ODBC > solution inherently slow? > > If nothing can be done to improve ODBC, I thought I could upload the > historical data into the local database and them use a > different source, say DDE, to update the real-time quotes for the current > day. Would that solution work? > > Please note that the historical data needs to be updated daily since it is a > total-return series. > > > > ------------------------------------ > > **** IMPORTANT PLEASE READ **** > This group is for the discussion between users only. > This is *NOT* technical support channel. > > TO GET TECHNICAL SUPPORT send an e-mail directly to > SUPPORT {at} amibroker.com > > TO SUBMIT SUGGESTIONS please use FEEDBACK CENTER at > http://www.amibroker.com/feedback/ > (submissions sent via other channels won't be considered) > > For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG: > http://www.amibroker.com/devlog/ > > Yahoo! Groups Links > > >
