DescribeQuery (children 1)
 TableExpression (children 1)
  Subquery (children 1)
   SelectWithUnionQuery (children 1)
    ExpressionList (children 1)
     SelectQuery (children 1)
      ExpressionList (children 2)
       Literal UInt64_1 (alias a)
       Function arrayMap (children 1)
        ExpressionList (children 2)
         Function lambda (children 1)
          ExpressionList (children 2)
           Function tuple (children 1)
            ExpressionList (children 1)
             Identifier x
           Function plus (children 1)
            ExpressionList (children 2)
             Identifier x
             Identifier a
         Literal Array_[UInt64_1, UInt64_2, UInt64_3]