map.sh

#!/bin/bash
set -e
set -x

MAP_FILE='./map'
DELIMITER=","
add (){
        KEY=$1
        VALUE=$2
        echo Key=$KEY Value=$VALUE
        KEY_EXITS=$(cat $MAP_FILE|cut -d $DELIMITER -f1|grep "^$KEY$"|wc -l)
        if [[ $KEY_EXITS -eq 0 ]]
        then
                NEW_LINE=${KEY}${DELIMITER}${VALUE}
        else
                LINE=$(cat $MAP_FILE|grep "^$KEY$DELIMITER"|tail -1)
                sed -i "/^$KEY$DELIMITER/d" $MAP_FILE
                VALUE_EXITS=$(echo $LINE|egrep "${DELIMITER}${VALUE}${DELIMITER}|${DELIMITER}${VALUE}$"|wc -l)
                if [[ $KEY_EXITS -eq 0 ]]
                then
                        NEW_LINE=${LINE}${DELIMITER}${VALUE}
                else
                        NEW_LINE=${LINE}
                fi
        fi
        echo "$NEW_LINE" >>$MAP_FILE
}
get (){
        KEY=$1
        VALUE=($(cat $MAP_FILE|grep "^$KEY"|tail -1| cut -d $DELIMITER -f 2- | tr $DELIMITER ' '))
}
add "cars" "bmw";
get "cars"
echo ${VALUE[1]}