一种矩阵具有相对较少的非零（或“有趣的” ）的项目。 It may be represented in much less than n × m space.它可派代表参加远远低于ñ ×米的空间。 -A matrix that has relatively few non-zero (or "interesting") entries. It may be represented in much less than n × m space.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.002008s ]
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:0.103083s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.002382s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.002197s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.006862s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.004063s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.002270s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003490s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.018003s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.003274s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 131144 [ RunTime:0.001241s ]
