The field is declared optional defensively because the outer sort carries NULLS LAST. The aggregate answers 0, not null, for a side with no rows.
0
Null when no marketplace is stored, and the empty string when the stored value is the default marketplace name. Both mean the same thing to a client.
Static
Return true if this struct equals the other.
Note: This compares the ABI encoded bytes of both structs, subclasses should implement their own fast equality check when possible.
The field is declared optional defensively because the outer sort carries NULLS LAST. The aggregate answers
0, not null, for a side with no rows.