Stephen Gutknecht (SAPDB) wrote: > My idea is to not do a full driver, just a highly optimized class that does > primarily one thing: returns DATASET objects from SELECT statements / > stored procedures from a SAPDB database. Just something to get around the > performance bottleneck for the most common operation in most web sites > (database reads). Fall back to using the ODBC.NET driver for all other > tasks (writes, cursors, etc).
- it will be difficult to have the two drivers share a session and thus transactions - Once you have translation of SQL values to .NET values and the reverse (for SELECTs with parameters), INSERTS and the likes are a cinch. > > Based on what I've studied with other drivers, there can be a 4x or higher > performance gain going with a native dotNet driver and not using the > ODBC.NET driver. This is the approach that some driver developers are > taking with PostgreSQL and MySQL, or at least the natural starting point. > > Any java programmers out there willing to help me get started? My first > goal is to figure out the existing code. First steps are how to assemble a > network packet to send to a SAPDB server. That means unraveling the > username/password SQL command encoding, assembling the packet, parsing back > the results. The lowest level of the JDBC driver has one flaw for your purpose: because Java doesn't have structs , let alone memcpy from raw memory into structs, the building and parsing of the network packets has to be done using offsets and byte per byte. This makes the code a bit clumsy, especially when taken as a reference implementation. And it makes the code quite slow. See sys/src/in/vin20* for a C++ version of that layer and http://sapdb.2scale.net/moin.cgi/NetworkProtocol for more information about the network protocol. > > SAP team... my questions about the future JDBC driver releases is still > unanswered. Please. The sources to a JDBC 3.0 driver are at ftp://ftp.sap.com/pub/sapdb/7.4. Daniel Dittmar -- Daniel Dittmar SAP DB, SAP Labs Berlin [EMAIL PROTECTED] http://www.sapdb.org _______________________________________________ sapdb.general mailing list [EMAIL PROTECTED] http://listserv.sap.com/mailman/listinfo/sapdb.general
