Before optimization:

After optimization:

When optimizing sql, we need to change our thinking and rewrite sql equivalently;

The rewritten sql has undergone earth-shaking changes due to logical reading, and the results are quickly obtained.

There is a function in the first sql execution plan, LNNVL("A"."APP_ID"<>:B1), lnnvl(exp)

If the result of exp is false or unknown, then lnnvl returns true;

If the result of exp is true, return false.