python运用mysql代码块，可跨文件调用

Posted 2021-09-27 被褐怀玉888988

本代码块将文件夹中id和对应文件名写入数据库。

import pymysql
import os

class database():
    def __init__(self,filename,user,passwd,db):
        self.filename=filename
        self.user = user
        self.passwd = passwd
        self.db = db
	#在main文件中调用该函数写入数据库
    def write(self):
        mi = pymysql.connect(host='localhost', user=self.user, passwd=self.passwd, db=self.db)
        cursor = mi.cursor()
        cursor.execute('DROP TABLE IF EXISTS Miwen')
        mi.close()
        id=0
        for i in os.listdir(filename):
            with open(filename+'/'+i,'r',encoding='utf-8') as f:
            	f.read()
                self.data(id,i)
            id=id+1 
               
    #写入数据库            
    def write_data(self,id,file_name):
        try:
        	#连接数据库
            mi = pymysql.connect(host='localhost', user=self.user, passwd=self.passwd, db=self.db)
         	#建立游标
            cursor = mi.cursor()
            #如果原来不存在该表格则创造表格
            sql= 'CREATE TABLE IF NOT EXISTS Miwen (id int,file_name varchar(64))'
            cursor.execute(sql)
            #插入id和file_name
            sqlQuery='INSERT INTO MIWEN(id,file_name)VALUE(%s,%s)'
            value=(id,file_name)
            cursor.execute(sqlQuery,value)
            
            mi.commit()
            cursor.close()
            mi.close()
        except pymysql.Error as e:
            print(str(e))
            
 	#查询文件是否存在，若存在则输出           
    def read_sql(j):
    	try:
        	mi = pymysql.connect(host='localhost', user=self.user, passwd=self.passwd, db=self.db)
        	cursor = mi.cursor()
        	#选择表格中的file_name
        	sql='SELECT file_name FROM miwen'
        	cursor.execute(sql)
        	result = cursor.fetchall()
        	j=j
        	for i in result:
            	i=str(i)[2:-3]
            	if i==j:
                	return i
        	print('该文件不存在')
    	except pymysql.Error as e:
        	print(str(e))