该程序完成对二叉树的非递归的前序遍历，在三种遍历方法中，这种遍历最简单，所以，核心代码自然要少很多。-completion of the process of non- recursive binary tree of the former preorder, the three traverse method, which traverse the most simple, so natural to the core code is much less.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001884s ]
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:0.111355s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.000860s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001122s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.000913s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003147s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000847s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003945s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.026216s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001139s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 117292 [ RunTime:0.012980s ]
