Description
string 
db2_conn_error ( [resource connection] )
   db2_conn_error() returns an SQLSTATE value representing
   the reason the last attempt to connect to a database failed. As
   db2_connect() returns FALSE in the event of a failed
   connection attempt, you do not pass any parameters to
   db2_conn_error() to retrieve the SQLSTATE value.
  
   If, however, the connection was successful but becomes invalid over time,
   you can pass the connection parameter to retrieve
   the SQLSTATE value for a specific connection.
  
   To learn what the SQLSTATE value means, you can issue the following command
   at a DB2 Command Line Processor prompt:
   db2 '? sqlstate-value'. You
   can also call db2_conn_errormsg() to retrieve an
   explicit error message and the associated SQLCODE value.