Python3 MySQL二 PyMySQL

目錄

 

1.數據庫連接

2.創建數據庫

3.插入數據

4.查詢

5.更新

6.刪除

7.執行事務

8.錯誤處理

9.整體總結 

---

user表 

1.數據庫連接

import pymysql

db = pymysql.connect("localhost", "user", "", "test")

cursor = db.cursor()

cursor.execute("select version()")
data = cursor.fetchone()
print("Database version : %s" % data)

db.close()

 運行結果:Database version : 10.1.37-MariaDB

2.創建表

import pymysql

db = pymysql.connect("localhost", "user", "", "test")

cursor = db.cursor()

cursor.execute("drop table if exists employee")
sql = """create table employee(
        name char(20) not null,
        sex char(1),
        income float )"""
cursor.execute(sql)

db.close()

 

3.插入數據

sql = "insert into employee(name, sex, income ) values ('周杰倫', 'M' ,1997)"
try:
    cursor.execute(sql)
    db.commit()
except:
    db.rollback()

db.close()

4.查詢

5.更新

cursor = db.cursor()
sql = "update employee set name = '你好22' where name = '你好'"
try:
    cursor.execute(sql)
    db.commit()
except:
   db.rollback()

db.close()

6.刪除

cursor = db.cursor()
sql = "delete from employee where income > %s" %(2000)
try:
    cursor.execute(sql)
    db.commit()
except:
   db.rollback()

db.close()

7.執行事務

8.錯誤處理

9.整體總結 

import pymysql

class DB():
    def __init__(self, host='localhost', port=3306, db='', user='root', passwd='root', charset='utf8'):
        # 建立連接 
        self.conn = pymysql.connect(host=host, port=port, db=db, user=user, passwd=passwd, charset=charset)
        # 創建遊標，操作設置爲字典類型        
        self.cur = self.conn.cursor(cursor = pymysql.cursors.DictCursor)

    def __enter__(self):
        # 返回遊標        
        return self.cur

    def __exit__(self, exc_type, exc_val, exc_tb):
        # 提交數據庫並執行        
        self.conn.commit()
        # 關閉遊標        
        self.cur.close()
        # 關閉數據庫連接        
        self.conn.close()


if __name__ == '__main__':
    with DB(host='192.168.68.129',user='root',passwd='zhumoran',db='text3') as db:
        db.execute('select * from course')
        print(db)
        for i in db:
            print(i)