Another, 4th approach (see in the above mentioned question) is to use filtered/partial unique indexes, if they are available in your DBMS (you'd need two of them, in table, for this case). This is very similar to the 3rd approach, except that you won't need the 2 extra tables. The "total participation" constraint has still to be applied by code.
The Himmeles wanted to be very clear: they’re not blaming teachers. They understand that the system of school does not support teachers in pursuing higher-level thinking and total participation in the classroom. Persida talked about how NCLB measures without providing supports and pathways. The testing pressure takes away time for kids to process information. And as educators, we often have no choice but to keep kids stuck in lower level thinking and minimal involvement because we have to hurry. The Himmele’s book works from the assumption that we have to trust the teachers and the kids.
|Weak entity type with identifying relationship|
The difference over the 1st and 2nd approach is that there are no circular FKs, so cascading updates and deletes will work just fine. The enforcement of "total participation" is not by DDL alone, as in 2nd approach, and has to be done by appropriate procedures (). A minor difference with the 2nd approach is that all the columns can be defined not nullable.
In my classroom, I'm always looking for ways to engage and involve all my students at the same time. Using total participation techniques, I am ens...