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  • python 连接数据库操作

    import mysql
    
    #打开数据库连接(用户名,密码,数据库名)
    db = mysql.connect("localhost","testuser","test123","testdb")
    
    #使用cursor()方法获取游标操作
    cursor = db.cursor()
    
    #使用exectue()执行sql语句操作
    cursor.excetue("select name from tmp where sex = "")

    #使用fetchone()方法获得一条数据 data = fetcone() print data db.close()

    python 连接创建数据库表

    db = connect("host","testuser","passwd","testdb")#连接数据库
    
    cursor = db.cursor()#连接游标
    
    
    
    sql = """crate table employee(
    
    FIRST_NAME CHAR(20) NOT NULL,
    
    LAST_NAME CHAR(20),
    
    AGE IN,
    
    SEX CHAR(1),
    
    INCOME FLOAT)""" 
    
    cursor.execute(sql)#执行SQL语句
    
    db.close()# 关闭数据库连接

    python 数据库插入操作

    import mysql
    
    db = mysql.connect("host","testuser","passwd","testdb")#连接数据库
    
    cursor = db.cursor()#获取游标
    
    sql = """
    insert into EMPLOYEE (FIRST_NAME,LAST_NAME,AGE,SEX,INCOME)
    VALUES("MAC","Mohan",20,"M",20000)
    """
    try:
      cursor.exceute(sql)#提行SQL语句
      db.commit()
    except:
      db.rollback()#发生错误回滚
    
    db.close()#关闭数据库连接

    数据库查询操作

    import mysql
    db = connect("host","testuser","passwd","testdb")
    cursor = db.cursor()
    #查询工资大于1000的员工信息
    sql = "select * from employee where sal>%d"%(1000)
    try:
        cursor.exceute(sql)#执行SQL语句
    
        results = cursor.fetchall#获取所有列表记录
        from row in results:
            fname = row[0]     
            lname = row[1]
            age = row[2]
            sex = row[2]
           ncome = rowp[4]
    
        print "fname = %s,lname = %s",age= %d,income = %d"
        %(fname,lname,age,sex,income)
    except:
        print "Error:unable to facth data"
    db.close()

    数据库更新操作

    import mysql
    
    db = connect ("host","testuser","passwd","testdb")#数据库连接
    surosr = db.cursor()#连接游标
    sql = "UPDATE EMPLOYEE" SET AGE = AGE +1 WHERE SEX = "%C"%(M)
    
    try:
      sursor.execute(sql)#执行数据库操作
      db.commit()
    except:
      db.rolloback()#发生错误时回滚
    db.close()#关闭数据库连接

    删除除操作

    import MYSQLdb
    
    db = connect("host","testuser","passwd","testdb")
    cursor = db.cursor()#连接游标
    sql = "DELETE FROM EMPLOYEE WHERE AGE >20"#删除年龄大于20岁的员工信息
    
    try:
      cursor.execute(sql)#执行SQL语句
      db.commit()
    except:
      db.rollback()#发生错误时回滚
    
    db.close()

      

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  • 原文地址:https://www.cnblogs.com/guog1/p/8508657.html
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