为存储磁盘或U盘更换盘符。比如：U盘插在PC机上显示的是F盘，可以被更换成H、G直到Z盘，只要该盘符空闲。-U for the storage disk or disk drive replacement. For example: U disk inserted in the PC, shows the F disk, can be replaced H, G until the Z disk, as long as the drive is idle.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001369s ]
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:0.088884s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001255s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001897s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001250s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003646s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.001107s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003221s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.014488s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001329s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 262141 [ RunTime:0.001160s ]
