Python - re-ordering columns in a csv

Question

I have a bunch of csv files with the same columns but in different order. We are trying to upload them with SQL*Plus but we need the columns with a fixed column arrange.

Example

required order: A B C D E F

csv file: A C D E B (sometimes a column is not in the csv because it is not available)

is it achievable with python? we are using Access+Macros to do it... but it is too time consuming

PS. Sorry if anyone get upset for my English skills.

Answer 1

You can use the csv module to read, reorder, and then and write your file.

Sample File:

$ cat file.csv A,B,C,D,E a1,b1,c1,d1,e1 a2,b2,c2,d2,e2 

Code

import csv  with open('file.csv', 'r') as infile, open('reordered.csv', 'a') as outfile:     # output dict needs a list for new column ordering     fieldnames = ['A', 'C', 'D', 'E', 'B']     writer = csv.DictWriter(outfile, fieldnames=fieldnames)     # reorder the header first     writer.writeheader()     for row in csv.DictReader(infile):         # writes the reordered rows to the new file         writer.writerow(row) 

output

$ cat reordered.csv A,C,D,E,B a1,c1,d1,e1,b1 a2,c2,d2,e2,b2