Read mysql column result in awk variable

I am unable to read single VALUE from mysql Query in awk.I am able to read it in bash but not in awk. I want to read the result variable in awk as I want to fire the query only based on some dynamic conditions written in awk.

awk '{
 cmd="(mysql --host='abc' --user='def' --password='..' --database='ghf' -sNe \"select VALUE from table where KEY='171-125';\")"
 cmd|getline $lastdiff;
 print "diff is "lastdiff;
}'


diff is

diff is

I have tried with grep -Eo \" [0-9]* \" also/ It is not helping. I have used both system() or cmd | getline to get the result into variable but it is always returning 0.

 sudo awk 'BEGIN {
>  myvalue=system("mysql --host='abc' --user='def' --password='..' --database='ghf' -sNe \"select VALUE from table where KEY='171-125';\" ");
>  print "diff is ",myvalue;
> }'
diff is  0

Bash is giving the result

mysql --host='abc' --user='def' --password='..' --database='ghf' -sNe "select VALUE from table where KEY='171-125';"
1

I want to read the numeric VALUE into lastdiff variable in awk. Any recommended solutions.