Abbreviated syntax of permutation

In records

I propose to write permutation as

select *
  from a, x
  where @a1~@x1 and @a2~@x1 and @a3~@x1;

select *
  from a
  where @a1<>@a2 and @a2<>@a3 and @a1<>@a3 and
    @a1 in (select @x1 from x) and
    @a2 in (select @x1 from x) and
    @a3 in (select @x1 from x);

Or for example

select @a1,@b1,@c1
  from a,b,c, x
  where @a1~@x1 and @b1~@x1 and @c1~@x1;

select @a1,@b1,@c1
  from a,b,c
  where @a1<>@b1 and @b1<>@c1 and @a1<>@c1 and
    @a1 in (select @x1 from x) and
    @b1 in (select @x1 from x) and
    @c1 in (select @x1 from x);

In rational or xml-tree

If abbreviated syntax of permutation for tree without spec-symbols

select *
  from a.b.c, x
  where a1~x1 and b1~x1 and c1~x1;

select *
  from a.b.c
  where a1<>b1 and b1<>c1 and a1<>c1 and
    a1 in (select x1 from x) and
    b1 in (select x1 from x) and
    c1 in (select x1 from x);

select *
  from a.b*.c, x
  where b1~x1;

select *
  from a.b[@b1 as k1].b[@b1 as m1].b[@b1 as n1].b[@b1 as p1].b[@b1 as q1].b[@b1 as r1].b[@b1 as s1]. ... .c
  where k1<>m1 and m1<>n1 and k1<>n1 and
    k1 in (select x1 from x) and
    m1 in (select x1 from x) and
    n1 in (select x1 from x) and
    p1 in (select x1 from x) and
    q1 in (select x1 from x) and
    r1 in (select x1 from x) and
    s1 in (select x1 from x) and ... ;

Dmitry Turin