[shmerl]

I don't get the point of the dummy value. How does it help doing anything? I can add conditions with ease without it.

[otteromkram]

Because any subsequent clauses usually start with AND, so if you're just checking data or validating it outside of production, it makes sense since you can comment to see lines you aren't checking out.

It also depends on how you write SQL, but not by much.

I wouldn't put a dummy variable into a finalized query.