头件的中的#ifndef，这是一个很关键的东西。比如你有两个C文件，这两个C文件都include了同一个头文件。而编译时，这两个C文件要一同编译成一个可运行文件，于是问题来了-The first pieces of# Ifndef, this is a very key things. For example, you have two C file, the two C files include the same file size. And compile-time, the two C files to compile together into a run file, then issue the
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001275s ]
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:0.056484s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001155s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001269s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001018s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003022s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000946s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003863s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.024385s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001856s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 109241 [ RunTime:0.087320s ]
