Python中的简易数据库shelve

Python中为我们提供了一个简易的数据库。内存中的数据随着我们程序的闭关就结束了它的生命周期。那么怎么样把数据持久化到文件和数据库呢？

shelve模块简易数据库，下面来一个例子：

                                         
import sys, shelve
def store_person(db):#存储人的信息
    """

    Query user for data and store it in the shelf object
    """
    pid = raw_input('Enter unique ID number: ')#主键
    person = {}
    person['name'] = raw_input('Enter name: ')
    person['age'] = raw_input('Enter age: ')
    person['phone'] = raw_input('Enter phone number: ')

    db[pid] = person

def lookup_person(db):#查询人信息
    """

    Query user for ID and desired field, and fetch the corresponding data from
    the shelf object
    """
    pid = raw_input('Enter unique ID number: ')
    temp = db[pid]
    field = raw_input('Please enter name, age or phone')
    field.strip().lower()
    print field.capitalize() + ': ',temp[field]

def enter_command():
    cmd = raw_input('Enter command')
    return cmd

def main():
    database = shelve.open('database')
    try:
        while True:
            cmd = enter_command()
            if cmd == 'store':
                store_person(database)
            elif cmd == 'lookup':
                lookup_person(database)
            elif cmd == 'quit':
                return
    finally:
        database.close()

if __name__ == '__main__': main()

OK,这样你的数据不会随程序的结束而销毁了，不信自己把数据存进去，下次启动的时候再查查看，还会有的！