sql-从链接创建类似结构的目录

Question

I have a table with column containing many URLs of various files, I want to create a directory like structure, folders and files sort of.

Folders first, then files

links
----------
http://abcd.com/efgh/hhg.txt
http://abcd.com/efgh/abc/bsbs/hsgs.txt
http://abcd.com/lmn.txt
http://abcd.com/jhksdh/khsdh/khd/abc.txt
http://abcd.com/dsfsdh/khsdh/dsfsdf/bsbs.txt

when entered http://abcd.com/ in query it should produce

╔════╦═════════════════╗
║    ║                 ║
╠════╬═════════════════╣
║  1 ║ efgh            ║
║  2 ║ jhksdh          ║
║  3 ║ dsfsdh          ║
║  4 ║ lmn.txt         ║
╚════╩═════════════════╝

when entered http://abcd.com/efgh/ in query it should produce

╔════╦═════════════════╗
║    ║                 ║
╠════╬═════════════════╣
║  1 ║ abc             ║
║  2 ║ hhg.txt         ║
╚════╩═════════════════╝

I can't make up a query using SUBSTRING_INDEX() string function

Answer 1

Is this close enough to what you want?

select l.*
from links l
where l.link like concat(@link, '/%')

I ask, because usually such a table would often (properly?) have all levels as separate rows. So, links would have rows for:

http://abcd.com/efgh/abc/bsbs/hsgs.txt
http://abcd.com/efgh/abc/bsbs
http://abcd.com/efgh/abc
http://abcd.com/efgh
http://abcd.com
http://

Then the following query does what you want:

select l.*
from links l
where l.link like concat(@link, '/%') and
      l.link not like concat(@link, '/%/%');

Without changing the data, this would generally work:

select concat(@link, '/',
              substring_index(substring(@link, length(@link) + 1
                                       ),
                              '/', 1
                             )
             )
from links l
where l.link like concat(@link, '/%');

Answer 2

Try this one

set @param = 'http://abcd.com/efgh/';
select 
distinct SUBSTRING_INDEX(REPLACE(link, @param, ''), '/', 1) as link 
from links 
where POSITION(@param IN link) > 0;