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disk I/O error with SQLite3 in Python 3 when writing to a database

i am a student just starting out with python, and i was tasked with creating a relational database management system. I think i came pretty far, but i seem to have hit a wall. This is my code:

import csv
import sqlite3

conn = sqlite3.connect('unfccc.db')
c = conn.cursor()

c.execute('''CREATE TABLE unfccc (
        Country TEXT, 
        CodeCountryFormat TEXT, 
        NamePollutant TEXT, 
        NameYearSector TEXT, 
        NameParent TEXT, 
        Sector TEXT, 
        CodeSector TEXT, 
        CNUEDSPD TEXT
        )''')

def insert_row(Country, CodeCountryFormat, NamePollutant, NameYearSector, NameParent, Sector, CodeSector, CNUEDSPD):
    c.execute("INSERT INTO unfccc VALUES (?, ?, ?, ?, ?, ?, ?, ?)", (Country, CodeCountryFormat, NamePollutant, NameYearSector, NameParent, Sector, CodeSector, CNUEDSPD))
    conn.commit()

with open('UNFCCC_v20.csv') as csvfile:
    readCSV = csv.reader(csvfile, delimiter='\t')

    counter = 0

    for row in readCSV:
        insert_row(row[0], row[1], row[2], row[3], row[4], row[5], row[6], row[7])
        counter = counter+1
        print('%d down, more to go' % counter)
conn.close()

when i run it with line 4 directing the input towards :memory: it works perfectly and i have myself what i think is a relational database.

However, when i try to run the code like this, writing the data to a db file, i get this error:

 File "<ipython-input-13-4c50216842bc>", line 19, in insert_row
    c.execute("INSERT INTO unfccc VALUES (?, ?, ?, ?, ?, ?, ?, ?)", (Country, CodeCountryFormat, NamePollutant, NameYearSector, NameParent, Sector, CodeSector, CNUEDSPD))

OperationalError: disk I/O error

I've searched stackoverflow, and i've used google, but i don't think any of the cases i found match up to what i'm trying to do here (or i don't have the knowledge to figure out whats going on). One other thing i noticed about my code is that it inputs the data into memory super fast, but when i write to a db file it is really slow, it shouldn't be a hardware limit as i am using an SSD. Any help will be greatly appreciated!

like image 762
Xander Blaauw Avatar asked Nov 28 '17 20:11

Xander Blaauw


2 Answers

Setting Backup/Sync to pause on the system tray icon while working with a project stored on Google Drive will prevent disk i/o errors.

This is because when the file is written to or changed, backup & sync attempts to upload the new version to your Google Drive, while it is doing this; the file becomes a 'Read-Only' file.

While sync is paused your Google Drive folder acts more like a normal directory.

(click -> settings -> pause/resume)

like image 108
Owen Easter Avatar answered Oct 15 '22 11:10

Owen Easter


I know I might be answering really late, but for others... I had the same problem, and the problem I found was that a python code was already using that database. When I stoped the code and ran the main code again, it did worked..

like image 26
RaPiDfire69 Avatar answered Oct 15 '22 11:10

RaPiDfire69