Please log separate JIRA cases for 1, 2, and a Quidem issue https://github.com/julianhyde/quidem/issues for 3.
1. I agree this is critical; but we should still check in a fix for 980.
2. IIRC we allow WHERE deptno = '50' as indeed we allow WHERE hireDate = '2015-01-01', and the semantics are to convert from string to numeric/date/time at run time, optimizing to compile time if the string is constant. That implies that we need to give run-time errors if the strings do not have valid format.
3. You could add a command-line flag for that behavior. By default, Quidem needs to be idempotent: if a Quidem test "fails" (i.e. does not behave as expected), it should generate a script such that if that script is run, it will "succeed". If a query produces different results than expected, the result should be the actual results. (If output is not ordered, Quidem tries to minimize the difference between the expected and actual.)