为一个字节或字符数组或串计算md5值，内部只创建一个数组，节省分配时间，节省内存 完全是static方法，线程安全 注意对返回值的处理，见注释-for a byte array or character string or md5 value calculation, only to create an internal array, saving time allocated to save memory is completely static method, thread-safe attention to the return value, see note
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001035s ]
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:0.062292s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001063s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001110s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.000998s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003168s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000892s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003888s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.015832s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001167s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 107036 [ RunTime:0.014808s ]
