SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 2)
   ExpressionList (children 2)
    Literal \'(0, C) id = 11\'
    Function count (children 1)
     ExpressionList
   TablesInSelectQuery (children 1)
    TablesInSelectQueryElement (children 1)
     TableExpression (children 1)
      Subquery (children 1)
       SelectWithUnionQuery (children 1)
        ExpressionList (children 1)
         SelectQuery (children 5)
          ExpressionList (children 2)
           Identifier id
           Function sequenceNextNode (alias next_node) (children 2)
            ExpressionList (children 4)
             Identifier dt
             Identifier action
             Literal UInt64_1
             Function equals (children 1)
              ExpressionList (children 2)
               Identifier action
               Literal \'C\'
            ExpressionList (children 2)
             Literal \'forward\'
             Literal \'head\'
          TablesInSelectQuery (children 1)
           TablesInSelectQueryElement (children 1)
            TableExpression (children 1)
             TableIdentifier test_sequenceNextNode_Nullable
          Function equals (children 1)
           ExpressionList (children 2)
            Identifier id
            Literal UInt64_11
          ExpressionList (children 1)
           Identifier id
          Function equals (children 1)
           ExpressionList (children 2)
            Identifier next_node
            Literal \'D\'
