%用法：[C，ptsC，centers]=dbscan（P，E，minPts）%%参数：%%P-dim x Npts点数组。%%E-距离阈值。%%minPts-形成簇所需的最小点数。%%返回：%%C-长度单元格数组与每个聚类%相关的点指数。%ptsC-列出与每个点%相关的聚类数的长度NPT数组。如果一个点被表示为噪声（在%附近不够）；&元素组成一个簇）它的簇数是0.centers-每个簇的平均中心的dim x Nc数组。
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001715s ]
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:0.084103s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.002316s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001835s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.002090s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003516s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.001893s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003169s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.014328s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.002428s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 10988 [ RunTime:0.001463s ]
