Only getting every nth value of each row in a csv file

Question

So I have a.csv file with 35 columns, some of which I want to write to a database.

I only need about 4 of these columns - is it possible to just write say the 3rd value, the 25th value, and the 29th value in each row to a MySQL database?

Either that, or can I only write where the values are "Year", "Amount", and "Whatever"?

Now I know I could just truncate the Excel file, but its for a college assignment so I wanted to show a "techy" solution.

Answer 1

Maybe something like this?

desired_rows = [...]  # Rows you'd like to read, 0-based
for number, row in enumerate(reader):
    if not number in desired_rows:
        continue

    # Do stuff with the rows you want
    ....

Answer 2

You could use operator.itemgetter to create a function that would retrieve all of the elements from each row each time it's called.

Something like the following. Note I subtract 1 from each column because the first column is at row index 0 , the second at index 1 , etc.

import csv
from operator import itemgetter

COLS = 3, 25, 29
filename = 'columns.csv'
getters = itemgetter(*(col-1 for col in COLS))

with open(filename, newline='') as csvfile:
    for row in csv.reader(csvfile):
        print(getters(row))