GROUP BY/SUM from shell

by

Edit: The modern (GNU/Linux) solution, as mentioned in comments years ago 😉 .

awk '{
    arr[$1]+=$2
   }
   END {
     for (key in arr) printf("%s\t%s\n", key, arr[key])
   }' file \
   | sort -k1,1

The originally posted solution, based on old Unix sort options:

awk '{
    arr[$1]+=$2
   }
   END {
     for (key in arr) printf("%s\t%s\n", key, arr[key])
   }' file \
   | sort +0n -1

I hope this helps.

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