python操作數據庫步驟以及操作過程中經常出現的異常

第一部分：dos窗口操作，創建相應數據庫、表 

1、進入mysql  ：mysql -uroot -p

2、查看所有數據庫：show batabases;

3、創建數據庫：create batabase test;

4、選擇數據庫： use test;

5、創建user表： CREATE TABLE `user` (  `uid` INT PRIMARY KEY AUTO_INCREMENT,  `uname` VARCHAR(30) NOT    NULL,  `pwd` VARCHAR(30) NOT NULL);

6、查看user表：desc user;

7、添加user表參數[uname,pwd] : insert into user(uname,pwd)values('tom','123');

異常示例：

第二部分：編寫相應腳本

注意: pip install MySQLdb

import MySQLdb

db = MySQLdb.Connect('localhost', 'root', 'root', 'test', charset='utf8')
# 使用 cursor() 方法創建一個游標對象cur
cur = db.cursor()  # 獲取游標
def select_sql(sql):

    # 使用 execute()  方法執行 SQL 查詢
    cur.execute(sql)
    # 使用 fetchall() 方法獲取查詢結果
    data = cur.fetchall()
    print(data)
    # 關閉數據庫連接
    db.close()

def update_sql(sql):
    try:
        cur.execute(sql)
        db.commit()
    except Exception as e:
        print('操作異常：%s'%str(e))
        db.rollback()
    db.close()
def select_sql2(sql):
    try:
        # 執行SQL語句
        cur.execute(sql)
        # 獲取所有記錄列表
        results = cur.fetchall()
        for row in results:
            uid = row[0]
            uname = row[1]
            pwd = row[2]
            # 打印結果
            print (uid, uname,pwd)
    except:
        print
        "Error: unable to fecth data"

    # 關閉數據庫連接
    db.close()
if __name__ == '__main__':
    sql1 = "insert into user(uname,pwd) values('jk4','123')"
    sql2 = "select * from user"
    sql3 = "select uname,pwd from user where uid=1"
    sql4 = "delete from user where uname='rows'"
    sql5 = "update user set pwd='666' where uname='jk3'"
    # update_sql(sql1)
    # select_sql(sql2)
    select_sql2(sql2)

異常：

TypeError: an integer is required (got type str) --- 添加charset='utf8'