poostenr added the comment: My initial observations with my Python script using:
s = "{0},".format(columnvalue) # fast Processed ~360MB of data from 2:16PM - 2:51PM (35 minutes, ~10MB/min) One particular file 6.5MB took ~1 minute. When I changed this line of code to: s = "'{0}',".format(columnvalue) # ~30x slower (1 min. vs 30 min.) Same particular file of 6.5MB took ~30 minutes (228KB/min). My Python environment is: C:\Data>python -V Python 3.5.1 :: Anaconda 2.4.1 (32-bit) I did some more testing with a very simplified piece of code, but is not conclusive. But there is a significant jump when I introduce the single quotes where I see a jump from 0m2.410s to 0m3.875s. $ python -V Python 3.5.1 // // s='test' // for x in range(10000000): // y = "{0}".format(s) $ time python test.py real 0m2.410s user 0m2.356s sys 0m0.048s // s='test' // for x in range(10000000): // y = "'%s'" % (s) $ time python test2.py real 0m2.510s user 0m2.453s sys 0m0.051s // s='test' // for x in range(10000000): // y = "'{0}'".format(s) $ time python test3.py real 0m3.875s user 0m3.819s sys 0m0.048s ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue26118> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com