Someone gave me a database. It's (1) a folder containing files with the following extensions: MYD, MYI, TRG, TRN, frm, opt; (2) a file with the sql-extension called db_add_nodata.sql , and (3) a file called sphinx.conf I have generated my database using the file with the sql-extension (am not sure what you call it, perhaps this file is called the sqldump?) in the following way: mysql -u root -p < db_add_nodata.sql Internally, it executes CREATE DATABASE 'technical1';. And I find the folder technical1 in my data dir /var/lib/mysql/technical1. I used the most recent version of the official documentation on the mysql website to try to create a soft link to the data which is on an external hard drive and mounted at such that the data are in /media/user/drive/data: $ mv technical1 /media/user/drive/ $ mv /media/user/drive/data/* /media/user/drive/technical1 $ ln -s /media/user/drive/technical1 /var/lib/mysql $ ls -lah technical1 drwx------ 2 mysql mysql 4.0K Jan 16 13:58 technical1 **Questions** - If I now execute the sql-statement SHOW DATABASES, the database technical1 is no longer showing up. Why's that? - Do the other steps look reasonable and correct, or can you see something else which looks odd?

Say I have a system that has Groups and Posts on those Groups. A Group can have multiple "child Groups" > Group 1 > Group 2 > Group 3 > Group 1 > Group 2 > Group 4 > Group 1 > Group 5 > Group 6 > ... So I have these two tables: Groups (*GroupId*, Name, ParentGroupId, ...) Posts (*PostId*, GroupId, UserId, Text, ...) Displaying a list of latest 10 posts on Group 3, 4 and 6 isn't a problem. An index on GroupId does it (WHERE GroupId=12345 ORDER BY PostId DESC). However, the challenge I'm having is how can I make Group 2 list posts created directly in Group 2, but also on children (Group 3 and 4), and the same for Group 1 (list posts on Group 1 and on all children, sorted). The only thing I can think of is to create an extra "indexing table" which will have a list of PostId for each Parent Group, and use that to retrieve the Posts. But, I'm afraid that will be a pain to maintain and ensure it's accurate (like using a TRIGGER). What if a bug happens and then we have to fix the index, rebuild the whole index again, etc... Is there a better way of doing this? I was hoping to use something more native and auto-maintained. I use MariaDB 10.4 and Sphinx Search.

I use SphinxSE instead of FULLTEXT. Sphinx settings are for end-users of a search engine. According to the official documentation , > LIMIT clause. Both LIMIT N and LIMIT M,N forms are supported. Unlike > in regular SQL (but like in Sphinx API), an implicit LIMIT 0,20 is > present by default. Therefore, any query returns only 20 rows MariaDB [sphinx]> SELECT * FROM t1 WHERE query='test;mode=any'; +------+--------+---------------+ | id | weight | query | +------+--------+---------------+ | 556 | 1 | test;mode=any | | 864 | 1 | test;mode=any | | 1329 | 1 | test;mode=any | | 1781 | 1 | test;mode=any | | 1832 | 1 | test;mode=any | | 2157 | 1 | test;mode=any | | 2388 | 1 | test;mode=any | | 2889 | 1 | test;mode=any | | 3118 | 1 | test;mode=any | | 3155 | 1 | test;mode=any | | 3255 | 1 | test;mode=any | | 3485 | 1 | test;mode=any | | 3495 | 1 | test;mode=any | | 3623 | 1 | test;mode=any | | 4034 | 1 | test;mode=any | | 4525 | 1 | test;mode=any | | 4563 | 1 | test;mode=any | | 4659 | 1 | test;mode=any | | 4736 | 1 | test;mode=any | | 4807 | 1 | test;mode=any | +------+--------+---------------+ 20 rows in set (0.027 sec) I experimented with various settings in the sphinx.conf, but am unable to change the setting to return more results in a SQL query.

On my Ubuntu 18.04 machine using mysql 5.7 I have installed sphinxsearch 2.2 and now I'd like to add SphinxSE as an engine so that I can connect to it without language-specific medium. The docs on sphinix is rather old (for MySQL 5.1.x) and involves compiling mysql from source which I shy away from as it may break the existing stuff. So I'm wondering if there is any straightforward solution for this which does not require source compilation?