How to pattern match against Unicode characters by PostgreSQL `SIMILAR TO` expressions?
Here is a check constraint:
CHECK (col ~ '^[0-9\u0660-\u0669\u06F0-\u06F9\u0966-\u096F]+$')

The pattern starts with &quot;beginning of string&quot; (^) and ends with &quot;end of string&quot; ($)and allows one or more &quot;digits&quot; in between.
^ and $ are necessary, otherwise the pattern would match abc123efg.