def openClose(fun):

    def run(sql=None):

        coon =pymysql.connect(host='localhost' ,port=3306 ,user='root', password='1234qwer', db='test', charset='utf8')

        cursor = coon.cursor()

        try:

            cursor.execute(fun( sql))

            data = cursor.fetchall()

            coon.commit()

            print(data)

        except Exception as e:

            coon.rollback()

            print('运行', str(fun), '方法时出现错误，错误代码：', e)

        finally:

            cursor.close()

            coon.close()

    return run

@openClose

def runSql(sql=None):

    if sql is None:

        sql = 'select * from students1'

    return sql

runSql()

runSql(‘select * from students1‘ where name= ‘tom1’)

添加时间记录功能

def openClose(fun):

    def run(sql=None):

        coon =pymysql.connect(host='localhost' ,port=3306 ,user='root', password='1234qwer', db='test', charset='utf8')

        cursor = coon.cursor()

        try:

            start_time = time.time()

            cursor.execute(fun( sql))

            data = cursor.fetchall()

            coon.commit()

            end_time = time.time()

            print('持续时间：'+str(end_time - start_time))

            print(data)

        except Exception as e:

            coon.rollback()

            print('运行', str(fun), '方法时出现错误，错误代码：', e)

        finally:

            cursor.close()

            coon.close()

    return run

@openClose

def runSql(sql=None):

    if sql is None:

        sql = 'select * from students1'

    return sql

runSql()

输出：

open_and_close_db  重要！重要！重要！

def open_and_close_db(do_sql):

    def wrapper(sql='select * from students1'):

        coon = pymysql.connect(host='localhost' ,port=3306 ,user='root', password='1234qwer', db='test', charset='utf8')

        cursor = coon.cursor()

        start_time = time.time()

        do_sql(cursor, coon, sql)

        cursor.close()

        coon.close()

        end_time = time.time()

        print('持续时间：' + str(end_time - start_time))

    return wrapper

@open_and_close_db

def do_sql(cursor,coon,sql):

    try:

        cursor.execute(sql)

        data = cursor.fetchall()

        coon.commit()

        print(data)

    except Exception as e:

        coon.rollback()

        print('运行时出现错误，错误代码：', e)

do_sql()

do_sql("update students1 set name = 'tom99999' where score = 44")