echo 'aabbccddDDCCDDCCaabbcc' | awk '{print $0, gsub("[a-z]", ".")}'

#!/usr/bin/ksh93

while read str num
do
   strU=${str//[^A-Z]}
   print "${str} ${#strU}"
done < file

aabbccddDDCCDDCCaabbcc 8
CCaaCCBBCCaaaaaaaCCCaa 11
CCDDCCAACCCCccccccccaa 12

# cat aaa
aabbccddDDCCDDCCaabbcc 123
CCaaCCBBCCaaaaaaaCCCaa 234
CCDDCCAACCCCccccccccaa 999

# for i in `cut -f1 aaa -d ' '`; do echo -n "$i "; echo -n $i | sed 's/[^a-z]//g' | wc -c; done
aabbccddDDCCDDCCaabbcc 14
CCaaCCBBCCaaaaaaaCCCaa 11
CCDDCCAACCCCccccccccaa 10