磁盘文件最优存储问题,设磁盘上有n 个文件f1, f1,fn,每个文件占磁盘上1 个磁道。这n 个文件的检索概率分别是p1, p2, , pn-document optimal disk storage, disk based on documents n f1, f1, fn. each file on disk for a cylinder. N This document retrieval probability were p1, p2, and pn
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.002081s ]
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:0.089857s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.002323s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001961s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.002278s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003886s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.002112s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003358s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.015020s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.002654s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 137755 [ RunTime:0.001227s ]