Function mz_sql::plan::statement::ddl::plan_drop_subsource

fn plan_drop_subsource(
    scx: &StatementContext<'_>,
    if_exists: bool,
    name: UnresolvedItemName,
    cascade: bool
) -> Result<Option<GlobalId>, PlanError>

Like plan_drop_item but specialized for the case of dropping subsources in response to ALTER SOURCE...DROP SUBSOURCE...