ORA-00020

Maximum number of Process reached.

You can check it by below query.

Query:

set lines 1000
select * from v$resource_limit;
select count(*),status from gv$session group by status;

Solution:

Actually, we need to kill unused processes.

And if the same error occurs again, we need to increase the parameter which needs bounce of database.

alter system set PROCESSES= <destination-value> scope = spfile;