实现了简单科学计算器的功能，可以使运用计算器简单功能的人受到很大方便。-achieve a simple scientific calculator function, we can make use of a simple calculator functions of the great convenience.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.094817s ]
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:0.153055s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.000975s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001161s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001135s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003211s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000980s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003959s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.015649s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001164s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 317211 [ RunTime:0.080994s ]
