InsertQuery   (children 2)
 Identifier lwd_test
 SelectWithUnionQuery (children 1)
  ExpressionList (children 1)
   SelectQuery (children 3)
    ExpressionList (children 2)
     Identifier number
     Function randomString (children 1)
      ExpressionList (children 1)
       Literal UInt64_10
    TablesInSelectQuery (children 1)
     TablesInSelectQueryElement (children 1)
      TableExpression (children 1)
       TableIdentifier system.numbers
    Literal UInt64_1000000