unique constraint definition within create table

Hi @ll,

i'm trying to create a table with 2 int-columns and a constraint that a
pair of (x,y) cannot be as (y,x) inserted:

test=# create table foo(u1 int,u2 int, unique (least(u1,u2),greatest(u1,u2)));
ERROR:  syntax error at or near "("
LINE 1: create table foo(u1 int,u2 int, unique (least(u1,u2),greates...


I know, i can solve that in this way:

test=*# create table foo(u1 int,u2 int);
CREATE TABLE
test=*# create unique index idx_foo on foo(least(u1,u2),greatest(u1,u2));
CREATE INDEX


But is there a way to define the unique constraint within the create table - command?

Thx.

Andreas
-- 
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