requirement:
1. compile time switch，runtime open/close,
1. severl log levels which can be set runtime
1. different category which can be set seperately
1. little influnce to performance
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.010883s ]
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:0.091381s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001526s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.002135s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.000957s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003525s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000927s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003836s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.016336s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.000997s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 292535 [ RunTime:0.038761s ]
