设计一个游标,其功能是按学号升序列出全体学生信息(学号、姓名、性别、专业)
时间: 2024-11-03 14:20:47 浏览: 25
设计一个游标(Cursor),用于按学号升序列出全体学生的信息,通常在数据库查询或编程环境中,游标是一种用于逐条获取结果集的机制。以下是使用伪代码描述一个基本的概念:
```python
class StudentCursor:
def __init__(self, database_connection):
self.conn = database_connection # 假设这是一个连接到数据库的对象
self.query = "SELECT student_id, name, gender, major FROM students ORDER BY student_id ASC"
def fetch_next_student(self):
"""获取并返回下一条学生记录"""
result = self.conn.execute(self.query)
if result.fetchone() is not None:
return result.fetchone()
else:
return None # 当所有数据都遍历完,返回None表示已无更多记录
def iterate_over_students(self):
"""生成器函数,按顺序获取所有学生信息直到数据耗尽"""
while True:
student = self.fetch_next_student()
if student is None:
break
yield student
# 使用示例
cursor = StudentCursor(database_connection)
for student_info in cursor.iterate_over_students():
print(f"学号:{student_info['student_id']},姓名:{student_info['name']},性别:{student_info['gender']},专业:{student_info['major']}")
```
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