EXEC_SQL loose Default_Connection

Question

hi,
as you suggested in a previous post ("DBMS_SQL signature error"), I replaced DBMS_SQL with EXEC_SQL package to run dynamic SQL. It works until I do SELECT queries. But I came into an issue when trying to run an UPDATE query.
This is my scenario (like in the previous thread). Pushing a button, procedure P is called
PROCEDURE P IS
BEGIN
--log out the current user and log on with another user
LOGOUT;
LOGON ('USER2','PWD2' || '@' || 'DB',FALSE);
UPDATE_PARAMS(....);
END;
PROCEDURE UPDATE_PARAMS(...) IS
     STR_QUERY      VARCHAR2(5000);
     connection_id      EXEC_SQL.CONNTYPE;
     cursorID      EXEC_SQL.CURSTYPE;
     bIsConnected      BOOLEAN;
     nRes           PLS_INTEGER;
BEGIN
     STR_QUERY := 'UPDATE MYTAB SET....';
     BEGIN
          CONNECTION_ID := EXEC_SQL.Default_Connection;
          IF NOT BISCONNECTED THEN
               MESSAGE('NOT CONNECTED');
          END IF;
          cursorID := EXEC_SQL.OPEN_CURSOR(connection_id);
          EXEC_SQL.PARSE(connection_id, cursorID, STR_QUERY, exec_sql.V7);                                   nRes := EXEC_SQL.EXECUTE(CONNECTION_ID,cursorID);
          EXEC_SQL.CLOSE_CURSOR(CURSORID);
     EXCEPTION
          when exec_sql.package_error then
               MESSAGE('Error in updating.'|| chr(10) || EXEC_SQL.LAST_ERROR_MESG(connection_id));
               EXEC_SQL.CLOSE_CURSOR(CURSORID);
               EXEC_SQL.CLOSE_CONNECTION(CONNECTION_ID);                    
               RAISE FORM_TRIGGER_FAILURE;
     END;
END;
This works on first call of P. If I push the button again, UPDATE_PARAMS cause an error due to the lack of connection. In fact, at the second call of UPDATE_PARAMS, the 'NOT CONNECTED' message is displayed. I tried to re-open the connection, but the error persists. How can I resolve this problem?

Answer 1

hi christian,
I will consider your suggestion of using DB Links instead of log out/log on approach. I must point out that USER1 and USER2 work on different Databases, and point to different report servers. What my application must do is this:
1) USER2 (from DB_2 and report Server 2) log on to application; then, send a request to USER1 (working on DB_1 and report Server 1) for him to run a report.
2) USER1 should log on to application, build parameter list for the report, run the report, and save the resulting PDF file into USER2 Database.
3) now, USER1 must disconnect, USER2 can relog on application and keep working.
So, while I guess USER2 could use a DB link to USER1's Database, I dont know what may happen if I try to call the report from USER2's connection. But above all, I wish to know why this approach works good in one environment (test environment) and doesnt in another.