Thank you all.

When you say most restrictive what does it mean, is it regarding the number of the rows it results?

In our case, using the following join:

Inner Join Terms t On t.schoolid = 0 And t.id = get_current_school_year()

The first join by schoolID will return much fewer records than the second one ID column.

So it means the schoolID is more restrictive, then we should put schoolID first , ID second.

It is different than what Jeff says.

Thanks,