python操作mysql数据库的相关操作实例

# -*- coding: utf-8 -*-

#python operate mysql database

import MySQLdb

#数据库名称

DATABASE_NAME = ''

#host = 'localhost' or '172.0.0.1'

HOST = ''

#端口号

PORT = ''

#用户名称

USER_NAME = ''

#数据库密码

PASSWORD = ''

#数据库编码

CHAR_SET = ''

#初始化参数

def init():

    global DATABASE_NAME

    DATABASE_NAME = 'test'

    global HOST

    HOST = 'localhost'

    global PORT

    PORT = ''

    global USER_NAME

    USER_NAME = 'root'

    global PASSWORD

    PASSWORD = 'root'

    global CHAR_SET

    CHAR_SET = 'utf8'

#获取数据库连接

def get_conn():

    init()

    return MySQLdb.connect(host = HOST, user = USER_NAME, passwd = PASSWORD, db = DATABASE_NAME, charset = CHAR_SET)

#获取cursor

def get_cursor(conn):

    return conn.cursor()

#关闭连接

def conn_close(conn):

    if conn != None:

        conn.close()

#关闭cursor

def cursor_close(cursor):

    if cursor != None:

        cursor.close()

#关闭所有

def close(cursor, conn):

    cursor_close(cursor)

    conn_close(conn)

#创建表

def create_table():

    sql = '''

    CREATE TABLE `student` (

    `id` int(11) NOT NULL,

    `name` varchar(20) NOT NULL,

    `age` int(11) DEFAULT NULL,

    PRIMARY KEY (`id`),

    UNIQUE KEY `name` (`name`)

    ) ENGINE=InnoDB DEFAULT CHARSET=utf8

    '''

    conn = get_conn()

    cursor = get_cursor(conn)

    result = cursor.execute(sql)

    conn.commit()

    close(cursor, conn)

    return result

#查询表信息

def query_table(table_name):

    if table_name != '':

        sql = 'select * from ' + table_name

        conn = get_conn()

        cursor = get_cursor(conn)

        result = cursor.execute(sql)

        for row in cursor.fetchall():

            print(row)

            #for r in row:      #循环每一条数据

                #print(r)

        close(cursor, conn)

    else:

        print('table name is empty!')

#插入数据

def insert_table():

    sql = 'insert into student(id, name, age) values(%s, %s, %s)'

    params = ('', 'Hongten_a', '')

    conn = get_conn()

    cursor = get_cursor(conn)

    result = cursor.execute(sql, params)

    conn.commit()

    close(cursor, conn)

    return result

#更新数据

def update_table():

    sql = 'update student set name = %s where id = 1'

    params = ('HONGTEN')

    conn = get_conn()

    cursor = get_cursor(conn)

    result = cursor.execute(sql, params)

    conn.commit()

    close(cursor, conn)

    return result

#删除数据

def delete_data():

    sql = 'delete from student where id = %s'

    params = ('')

    conn = get_conn()

    cursor = get_cursor(conn)

    result = cursor.execute(sql, params)

    conn.commit()

    close(cursor, conn)

    return result

#数据库连接信息

def print_info():

    print('数据库连接信息:' + DATABASE_NAME + HOST + PORT + USER_NAME + PASSWORD + CHAR_SET)

#打印出数据库中表情况

def show_databases():

    sql = 'show databases'

    conn = get_conn()

    cursor = get_cursor(conn)

    result = cursor.execute(sql)

    for row in cursor.fetchall():

        print(row)

#数据库中表情况

def show_tables():

    sql = 'show tables'

    conn = get_conn()

    cursor = get_cursor(conn)

    result = cursor.execute(sql)

    for row in cursor.fetchall():

        print(row)

def main():

    show_tables()

    #创建表

    result = create_table()

    print(result)

    #查询表

    query_table('student')

    #插入数据

    print(insert_table())

    print('插入数据后....')

    query_table('student')

    #更新数据

    print(update_table())

    print('更新数据后....')

    query_table('student')

    #删除数据

    delete_data()

    print('删除数据后....')

    query_table('student')

    print_info()

    #数据库中表情况

    show_tables()

if __name__ == '__main__':

    main()