SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 3)
   ExpressionList (children 1)
    Function equals (children 1)
     ExpressionList (children 2)
      Identifier day
      Literal \'2020-01-01\'
   TablesInSelectQuery (children 2)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (alias a) (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 4)
          ExpressionList (children 1)
           Identifier day
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier test_table
          Function equals (children 1)
           ExpressionList (children 2)
            Identifier day
            Literal \'2020-01-01\'
          ExpressionList (children 1)
           Identifier day
    TablesInSelectQueryElement (children 2)
     TableExpression (children 1)
      Subquery (alias b) (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 2)
          ExpressionList (children 1)
           Function toDate (alias day) (children 1)
            ExpressionList (children 1)
             Literal \'2020-01-01\'
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             Function numbers (children 1)
              ExpressionList (children 1)
               Literal UInt64_1
     TableJoin (children 1)
      Function equals (children 1)
       ExpressionList (children 2)
        Identifier a.day
        Identifier b.day
   Set