Python - How to make data append instead of overwrite?

Question

Within my code, I need my Name and Score field names to stay the same. However, when adding a row on the last line of code, I want this to append the csv, whereas it's currently overwriting the last entry.

with open("class1.csv", 'w') as csvfile:
    fieldnames = ["Name", "Score"]
    writer = csv.DictWriter(csvfile, fieldnames=fieldnames)
    writer.writeheader()
    writer.writerow({'Name': name, 'Score': score})

score 2 · Answer 1 · answered Apr 18 '16 at 18:11

2

Use open("class1.csv", 'a') instead of open("class1.csv", 'w')

answered Apr 18 '16 at 18:11

Peaceful

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Sorry that doesn't work! It appends both the headings and the data entries, whereas I only need the data entries to append, otherwise multiple field names are in the csv file. – Adam Apr 18 '16 at 18:17
You mean that you want `name` to be in the file but not not `Name` for example? – Peaceful Apr 18 '16 at 18:22
@Adam Don't call `writeheader()`, since the file already has a header. – Barmar Apr 18 '16 at 18:28
@Snehal Shekatkar Yeah that's right! – Adam Apr 18 '16 at 18:34
@Barmar Right ok, makes sense! But what about if I'm creating the file for the first time, it won't have the header? – Adam Apr 18 '16 at 18:35
@Adam Check whether the file already exists first. – Barmar Apr 18 '16 at 18:37

Python - How to make data append instead of overwrite?

1 Answers1