PI JDBC uses PI SQL DAS for its service layer. I'm not aware of a hard limit for concurrent connections to PI SQL DAS, but it was not designed to handle a large number of parallel connections. For a large user base, you can consider configuring a limited number of PI SQL DAS instances and dividing your users among them. Is there a particular error you are encountering?
I don't have any issue by the moment, I have a client that made this question and I respond something similar at your answer, but I wish to know the limitation of PI JDBC.
It is not PI JDBC driver it-self's limitation but for creating connection, PI JDBC also use port. If ports exhaustion occurs, it will be limitation.
The default value is 5000.
In that case, you can change Max port number.
Also PI Server (PI Data Archive) have limitation of connections. Limitation number is 32767 if you use later than 3.4.380.36.
You can also take a look at the Session ID parameter to group server connections for them to be serialized if you do not want to exhaust the number of connections (32767) to the server.