Macro owner_reassignment 

macro_rules! owner_reassignment {
    (
        $vis:vis struct $name:ident;
        domain = $domain:literal;
        $( $kind:ident $table:literal => $sql:literal; )+
    ) => { ... };
    (@step update $tx:ident $from:ident $to:ident $sql:literal) => { ... };
    (@step delete $tx:ident $from:ident $to:ident $sql:literal) => { ... };
}