{ expr 
   { = | != | ^= | <> | > | < | >= | <= } 
   { ANY | SOME | ALL } 
   ( { expression_list | subquery } )
| expr [, expr ]... 
   { = | != | ^= | <> }
   { ANY | SOME | ALL } 
   ( { expression_list [, expression_list ]...
     | subquery } )
}