C51的一些误区和注意事项（ZT）
1)C忌讳绝对定位。 常看见初学者要求使用_at_,这是一种谬误，把C当作ASM看待了。在C中变量
的定位是编译器的事情，初学者只要定义变量和变量的作 用域，编译器就把一个固定地址给这个
变量。怎么取得这个变量的地址？要用指针。比如unsigned char data x 后，x的地址就是...
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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:0.097153s ]
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SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.000965s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.003104s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.000873s ]
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SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.014999s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001269s ]
UPDATE `jrk_articles` SET `hits` = 2 WHERE `id` = 514154 [ RunTime:0.963258s ]
