Is it possible in Nginx to limit the total number of queries?

With nginx it is possible to set a limit on the number of requests from one ip:

limit_req_zone $binary_remote_addr zone=zzz:10m;
...
"limit_req" zone=zzz burst=1000 nodelay;

Is there in nginx such a limitation, but for the total number of queries instead a single ip? And could this be considered as part of the system of protection against DDOS?