SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 1)
    Function uniqUpTo (children 2)
     ExpressionList (children 2)
      Identifier x
      Function arrayMap (children 1)
       ExpressionList (children 2)
        Function lambda (children 1)
         ExpressionList (children 2)
          Function tuple (children 1)
           ExpressionList (children 1)
            Identifier elem
          Function array (children 1)
           ExpressionList (children 2)
            Identifier elem
            Identifier elem
        Identifier x
     ExpressionList (children 1)
      Literal UInt64_3
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 1)
          ExpressionList (children 1)
           Function arrayJoin (alias x) (children 1)
            ExpressionList (children 1)
             Function array (children 1)
              ExpressionList (children 4)
               Function array (children 1)
                ExpressionList
               Literal Array_[\'a\']
               Literal Array_[\'a\', \'b\']
               Function array (children 1)
                ExpressionList
