电子时钟的设计：
要求：
设计一个电子时钟。
要求可以显示时、分、秒。
用户可以设置时间。-Electronic clock design: requirements: design of an electronic clock. Required to display hours, minutes and seconds. Users can set the time.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001954s ]
SELECT `a`.`aid`,`a`.`title`,`a`.`create_time`,`m`.`username` FROM `jrk_downrecords` `a` INNER JOIN `jrk_member` `m` ON `a`.`uid`=`m`.`id` WHERE `a`.`status` = 1 GROUP BY `a`.`aid` ORDER BY `a`.`create_time` DESC LIMIT 10 [ RunTime:0.085392s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.002308s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001949s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.002298s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003899s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.001999s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003508s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.015711s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.003386s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 238335 [ RunTime:0.001145s ]
