[Monetdb-developers] final execution plan
hello, can anyone tell me how in monetdb/xquery we can see what is the final plan with the help of which query is executed i.e how can i find the plan generated at run time for query execution (which tells that which join operation is performed at particular node). The INTERNET now has a personality. YOURS! See your Yahoo! Homepage. http://in.yahoo.com/
On Thu, Mar 11, 2010 at 11:13:20AM +0530, Puneet Birwa wrote:
hello, can anyone tell me how in monetdb/xquery we can see what is the final plan with the help of which query is executed i.e how can i find the plan generated at run time for query execution (which tells that which join operation is performed at particular node).
you can use 'pf', the stand-alone version of the Pathfinder XQuery compiler to see the generated MIL plan. See `pf --help` and `pf --fullhelp` for details. Except from choosing algorithms and implementations based on the properties of operators' actual input(s) at runtime, the physical algebra plan (MIL program) is executed as is. Choosing the algorithms and implementations is done inside the operators' implementations (see e.g., the code in MonetDB/src/gdk/relop.(mx|c)), and can only be traced by single-stepping the execution in a debugger or by enabling debugging output via the Mserver commandline option --debug=2097152 (see MonetDB4/conf/MonetDB.conf[.in] or <fix>/etc/MonetDB.conf for all available debug options.) Stefan -- | Dr. Stefan Manegold | mailto:Stefan.Manegold@cwi.nl | | CWI, P.O.Box 94079 | http://www.cwi.nl/~manegold/ | | 1090 GB Amsterdam | Tel.: +31 (20) 592-4212 | | The Netherlands | Fax : +31 (20) 592-4199 |
participants (2)
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Puneet Birwa
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Stefan Manegold