调用类，获取TypeError：必须调用未绑定的方法

Question

我已经查看了Stackoverflow上的错误，但是我没有看到任何解决方案可以解决我的问题。我正在尝试为cx_Oracle创建一个类，以将我的数据库连接置于类中，并在我的数据库实例中调用它。 我在C＃中创建了类似的类，但由于某种原因python特别困难。任何援助赞赏。

我杠杆这里找到这段代码： cx_Oracle and Exception Handling - Good practices?

import sys 
    import os 
    import cx_Oracle 

    class Oracle(object): 

     __db_server = os.getenv("ORACLE_SERVER") 
     __db_user = os.getenv("ORACLE_ACCT") 
     __db_password = os.getenv("ORACLE_PWD") 

     def connect(self): 
      """ Connect to the database. """ 

      try: 
       self.db = cx_Oracle.connect(__db_user+'/'+__db_password+'@'+__db_server) 
      except cx_Oracle.DatabaseError as e: 
       error, = e.args 
       if error.code == 1017: 
        print('Please check your credentials.') 
       else: 
        print('Database connection error: %s'.format(e)) 
       # Very important part! 
       raise 

      # If the database connection succeeded create the cursor 
      # we-re going to use. 
      self.cursor = db.Cursor() 

     def disconnect(self): 
      """ 
      Disconnect from the database. If this fails, for instance 
      if the connection instance doesn't exist we don't really care. 
      """ 

      try: 
       self.cursor.close() 
       self.db.close() 
      except cx_Oracle.DatabaseError: 
       pass 

     def execute(self, sql, bindvars=None, commit=False): 
      """ 
      Execute whatever SQL statements are passed to the method; 
      commit if specified. Do not specify fetchall() in here as 
      the SQL statement may not be a select. 
      bindvars is a dictionary of variables you pass to execute. 
      """ 

      try: 
       self.cursor.execute(sql, bindvars) 
      except cx_Oracle.DatabaseError as e: 
       error, = e.args 
       if error.code == 955: 
        print('Table already exists') 
       elif error.code == 1031: 
        print("Insufficient privileges") 
       print(error.code) 
       print(error.message) 
       print(error.context) 

       # Raise the exception. 
       raise 

      # Only commit if it-s necessary. 
      if commit: 
       self.db.commit() 

     def select(self, sql, commit=False):   
      bindvars=None 
      result = None 
      try: 
       self.cursor.execute(sql, bindvars) 
       result = self.cursor.fetchall() 
      except cx_Oracle.DatabaseError as e: 
       error, = e.args 
       print "Database Error: failed with error code:%d - %s" % (error.code, error.message) 
       raise 
      if commit: 
       self.db.commit() 
      return result 

     def commit(self): 
      try: 
       self.db.commit() 
      except cx_Oracle.DatabaseError as e: 
       error, = e.args 
       print "Database Commit failed with error code:%d - %s" % (error.code, error.message) 
       raise 

     def rollback(self): 
      try: 
       self.db.rollback() 
      except cx_Oracle.DatabaseError as e: 
       error, = e.args 
       print "Database Rollback failed with error code:%d - %s" %(error.code, error.message) 
       raise 

这是我的调用程序

import sys 
    import os 
    #import cx_Oracle 
    from Oracle import Oracle 

    def main(): 
     oracle = Oracle.connect() 
     query = """SELECT DISTINCT NAME FROM MyTable""" 
     data = oracle.select(query) 
     for row in data: 
      print row 
     oracle.disconnect() 

    ### MAIN 
    if __name__ == '__main__': 
     main() 

相关提示：我似乎无法让Python找到我的Oracle .py类，除非它与调用函数位于同一目录中。

艾伦

Answer 1

你必须创建类的实例来使用它：

orcl = Oracle() 
orcl.connect() 
...