主要实现集合的交集、并集、差集，可获集合的交集、并集、差集。-To achieve the intersection of the main collections, and sets, difference sets, be the intersection of sets, and sets, difference sets.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001074s ]
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:0.074467s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001003s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001110s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.000954s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003833s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.001450s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.008587s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.018010s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001250s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 314577 [ RunTime:0.013912s ]
