Oracle PL/SQL for DBAs

Interpreting Errors

The most common error you will encounter, and the easiest to deal with, is ORA-28110: Policy function or package has error. The culprit here is a policy function with one or more compilation errors. Fixing your compilation errors and recompiling the function (or the package containing the function) solves the problem.

You may also encounter runtime errors, such as an unhandled exception, a datatype mismatch, or a situation in which the fetched data is much larger than the variable fetched into. In these cases, Oracle raises the ORA-28112: failed to execute policy function error and produces a trace file. You can examine that file, which you will find in the directory specified by the USER_DUMP_DEST database initialization parameter, to find out the nature of the error. Here is an excerpt from a trace file.

    Policy function execution error:
    Logon user     : MARTIN
    Table/View     : HR.EMP
    Policy name    : EMP_DEPT_POLICY
    Policy function: RLSOWNER.AUTHORIZED_EMPS
    ORA-01422: exact fetch returns more than requested number of rows
    ORA-06512: at "RLSOWNER.AUTHORIZED_EMPS", line 14
    ORA-06512: at line 1

The trace file shows that Martin was executing the query when this error occurred. Here the policy function simply fetched more than one row. Examining the policy function, you notice that the policy function has a segment as follows.

    SELECT deptno
    INTO l_deptno
    FROM hr.emp
    WHERE ename = USER;

It seems there is more than one employee with the name Martin—hence, the number of rows fetched ...