Hi John, I'll look into it. We could add an option to Query() that will tell the DB systems to return row-by-row. I'll investigate. Cheers, Fons. On Wed, 2003-07-09 at 23:34, Dr. John Krane wrote: > Hi, > > I just spent the day adding a 30GB swap area (!) to my machine so I > could query my server with TSQLServer without crashing. Unfortunately, > I just crashed again with an out-of-memory error. > > Per Fons, the code collects the data in RAM and swap and then you use > TSQLRow (I think that's the class) to get row by row. A db connection > in MySQL would looks like: > > mysql -h myhostname -u myusername -p > > If I put a "-q" in front of the "-h", then the db would give me > row-by-row as it found them instead of building up the huge (HUGE!) > buffer first and giving me the rows second. Unfortunately, in root you > are stuck with > > TSQLServer("myhostname", "myusername", "mypassword") > > ...with no place for the -q option and no code in the class to do > anything with it. May I please request the author revisit the > TSQLServer class to perhaps allow "-q" or some form of block transfers > ...I am stuffing swap to the bursting...and beyond. > > (Although in MySQL it is possible to "limit 100000" or something to get > the first N events, it is not to my knowledge possible to skip those > same events when you come back for the remainder. So I don't really > have much of a way around this.) > > - John -- Org: CERN, European Laboratory for Particle Physics. Mail: 1211 Geneve 23, Switzerland E-Mail: Fons.Rademakers@cern.ch Phone: +41 22 7679248 WWW: http://root.cern.ch/~rdm/ Fax: +41 22 7679480
This archive was generated by hypermail 2b29 : Thu Jan 01 2004 - 17:50:13 MET