How do quickly search through a .csv file in Python

Question

I\'m reading a 6 million entry .csv file with Python, and I want to be able to search through this file for a particular entry.

Are there any tricks to search the en

Answer 1

you can use memory mapping for really big files

import mmap,os,re
reportFile = open( "big_file" )
length = os.fstat( reportFile.fileno() ).st_size
try:
    mapping = mmap.mmap( reportFile.fileno(), length, mmap.MAP_PRIVATE, mmap.PROT_READ )
except AttributeError:
    mapping = mmap.mmap( reportFile.fileno(), 0, None, mmap.ACCESS_READ )
data = mapping.read(length)
pat =re.compile("b.+",re.M|re.DOTALL) # compile your pattern here.
print pat.findall(data)