Generic JDBC Exception

Question

Hi all, 
 While trying to open search screen I am seeing the below error message. 
 'Could not open JPA EntityManager for transaction; nested exception is javax.persistence.PersistenceException: org.hibernate.exception.GenericJDBCException: Cannot open connection'

I checked for AppianBusinessDS connection and it looks fine. 
 Can someone please let me know how to move forward with this issue. 
 
 Thanks in Advance.

aloks0189 · Answer

Hi Muneer Varma there are many factors which leads to this Exception while working with JPA, those are: -> When your DB url is incorrect/mismatched -> When your DB driver class name is incorrect/mismatched -> When you have configured for max-pool-size are used up and wait time for getting it (hoping that something gets returned into pool) has expired. So in such case try increasing max-pool-size to something bigger as per the number of Concurrent users (or) time taking to perform transaction (if any). 
 
 Hope this will help you.