Which rows slip through when active is unknown?

Question

Accepted Answer

The WHERE clause passes rows where the full condition is true. For id=1: TRUE = TRUE is true, so the row is included. For id=2: FALSE = TRUE is false, and FALSE IS NULL is false - the row is excluded. For id=3: NULL = TRUE is NULL (not true), but NULL IS NULL is true - the OR short-circuits to true, so the row is included. This pattern is useful when NULL means 'treat as active'.