教学＂求圆的面积和圆的周长＂的程序，给学生作为一个简单的例子讲解．-Teaching for a round the area and circumference of a circle of the procedures available to the students as a simple example to explain.
SHOW FULL COLUMNS FROM `jrk_downrecords` [ RunTime:0.001253s ]
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:0.088623s ]
SHOW FULL COLUMNS FROM `jrk_tagrecords` [ RunTime:0.001182s ]
SELECT * FROM `jrk_tagrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 20 [ RunTime:0.001953s ]
SHOW FULL COLUMNS FROM `jrk_member` [ RunTime:0.001229s ]
SELECT `id`,`username`,`userhead`,`usertime` FROM `jrk_member` WHERE `status` = 1 ORDER BY `usertime` DESC LIMIT 10 [ RunTime:0.004944s ]
SHOW FULL COLUMNS FROM `jrk_searchrecords` [ RunTime:0.001040s ]
SELECT * FROM `jrk_searchrecords` WHERE `status` = 1 ORDER BY `num` DESC LIMIT 5 [ RunTime:0.003193s ]
SELECT aid,title,count(aid) as c FROM `jrk_downrecords` GROUP BY `aid` ORDER BY `c` DESC LIMIT 10 [ RunTime:0.014818s ]
SHOW FULL COLUMNS FROM `jrk_articles` [ RunTime:0.001270s ]
UPDATE `jrk_articles` SET `hits` = 1 WHERE `id` = 174954 [ RunTime:0.001628s ]
