#!/bin/bash
 
# ideone boilerplate - we can't write files in the home directory;
# so create a temporary directory for our files instead
t=$(mktemp -d -t ideone.XXXXXXXXXXXX) || exit
trap 'rm -rf "$t"' ERR EXIT
cd "$t"
 
cat <<\: >zulu_db_capcodes.txt
capcode,discipline,region,location,description,remark
000400001,Brandweer,Groningen,Groningen,Regionaal,Pelotonscommandant Logistiek/Water (Noord)
000400002,Brandweer,Groningen,Groningen,,
000400003,Brandweer,Groningen,Groningen,Regionaal,Pelotonscommandant Logistiek/Water) (Oost)
000100000,Brandweer,Amsterdam-Amstelland,Amsterdam-Amstelland,Aalsmeer,Postalarm
000100001,Brandweer,Amsterdam-Amstelland,Amsterdam-Amstelland,,
000100002,Brandweer,Amsterdam-Amstelland,Amsterdam-Amstelland,,Banaanzulu
000100003,Brandweer,Amsterdam-Amstelland,Amsterdam-Amstelland,,
:
 
cat <<\: >bommel_db_capcodes.txt
capcode,discipline,region,location,description,remark
000100000,Brandweer,Amsterdam-Amstelland,,banaanProefalarm,
000100001,Brandweer,Amsterdam-Amstelland,Aalsmeer,Bevelvoerders,
000100004,Brandweer,Amsterdam-Amstelland,Aalsmeer,Korpsalarm,
:
 
cat <<\: >demo.py
#!/usr/bin/env python3
import csv
 
 
fields = ['capcode', 'discipline', 'region', 'location', 'description', 'remark']
 
with open('bommel_db_capcodes.txt', 'r') as readFile_bommel, \
        open('results.csv', 'w') as results, \
        open('zulu_db_capcodes.txt', 'r') as readFile_zulu:
 
    master = csv.DictReader(readFile_zulu, fieldnames=fields)
    update = csv.DictReader(readFile_bommel, fieldnames=fields)
    writer = csv.DictWriter(results, fieldnames=fields)
 
    # Saves and skips header to output file
    writer.writerow(next(master))
 
    # Skip header from updates
    next(update)
 
    # Read, remember, and write updated lines
    seen = set()
    for row in update:
        writer.writerow(row)
        seen.add(row['capcode'])
 
    for row in master:
        if row['capcode'] not in seen:
            writer.writerow(row)
:
 
python3 demo.py
 
nl results.csv

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