树的四种遍历方式,中叙,前序,后序和按层遍历算法,前三个用递归很好实现,最后一个复杂点。-tree traversal of the four, China and Syria, the former sequence after sequence and by layer traversal algorithm, the former three Recursive properly achieved, Finally a complex point.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001299s ]
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:0.115635s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001189s ]
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SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001167s ]
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SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.001017s ]
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SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001578s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 301619 [ RunTime:0.001383s ]