linux-0.11调试教程

<?php /* * PHP code to export MySQL data to CSV * * Sends the result of a MySQL query as a CSV file for download * Easy to convert to UTF-8. */ /* * establish database connection */ $link = mysqli_connect("localhost", "my_user", "my_password".

selectnndas'年龄段',sum(人数)as'年龄段人数'from(selectcasewhen年龄>21and年龄<=25then'21-25'when年龄>26and年龄<=30then'26-30'when年龄>31and年龄<=35then'31-35'when年龄>36and年龄<=40then'36-40'else'other'endasnnd,人数from...

SELECT count(*),`订书编号` FROM `TABLE 20` GROUP BY `订书编号` 教师节学校给老师订书，每个人一本。 一共有51种书，学校想统计一个订书编号位N的书共订了几本？ 一个小栗子： 张三 2 李四 3 王五 3 赵六 1 杨七 4 周八 1 白九 1 结果是： count(*)`订书编号` 3 ...