mysql> select SUBSTR(domain,1,LOCATE('.',domain)-1) pre,count(*) c from sys_domain where parent_id > 0 group by pre order by c desc limit 0,3000;
+----------------+---------+
| pre            | c       |
+----------------+---------+
| www            | 1024282 |
| mail           |  451476 |
| ftp            |  187225 |
| smtp           |  169424 |
| pop            |  140343 |
| m              |   79738 |
| webmail        |   76103 |
| pop3           |   56713 |
| imap           |   45873 |
| localhost      |   44444 |
| autodiscover   |   39349 |
| admin          |   34667 |
| bbs            |   33637 |
| test           |   33279 |
| mx             |   29939 |
| en             |   29384 |
| email          |   28887 |
| wap            |   27455 |
| blog           |   25578 |
| oa             |   25277 |
| ns1            |   22630 |
| vpn            |   22311 |
| ns2            |   22140 |
| www2           |   21640 |
| mysql          |   21575 |
| webdisk        |   19663 |
| dev            |   18736 |
| old            |   17895 |
| news           |   17740 |
| calendar       |   16481 |
| shop           |   16124 |
| potala         |   15975 |
| mobile         |   15588 |
| web            |   15569 |
| sip            |   15567 |
| mobilemail     |   15445 |
..........

domain.txt

子域名前缀top3000-新