大约有 7,000 项符合查询结果（耗时：0.0173秒） [XML]
How to filter SQL results in a has-many-through relation
...on easier to extend to n clubs and that avoids INTERSECT (not available in MySQL) and IN (as performance of this sucks in MySQL)
SELECT s.id,
s.name
FROM student s
join student_club sc
ON s.id = sc.student_id
WHERE sc.club_id IN ( 30, 50 )
GROUP BY s.id,
s.name
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jQuery dot in ID selector? [duplicate]
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Use the escaping rules from the jQuery selectors API as follows:
$('#root\\.SomeCoolThing')
From the docs:
To use any of the meta-characters (such as
!"#$%&'()*+,./:;<=>?@[\]^`{|}~) as a literal part of a name, it must
be escaped with with two backslashes: \\. For example...
Problems with contenttypes when loading a fixture in Django
I am having trouble loading Django fixtures into my MySQL database because of contenttypes conflicts. First I tried dumping the data from only my app like this:
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Best practices when running Node.js with port 80 (Ubuntu / Linode) [closed]
...You don't need sudo in /etc/rc.local because the commands there are run as root when the system boots.
Logs
Use the forever module to launch your Node.js with. It will make sure that it restarts if it ever crashes and it will redirect console logs to a file.
Launch on Boot
Add your Node.js start sc...
How do you attach and detach from Docker's process?
...l+p + Ctrl+q to quit the container:
# docker exec -it 91262536f7c9 bash
root@91262536f7c9:/# ps -aux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.0 18160 1908 ? Ss+ 04:03 0:00 /bin/bash
root 15 0.0 0.0 18164 1892 ? S...
Finding duplicate values in a SQL table
...QL Server 2017) still requires all non-aggregated columns in the GROUP BY.
MySQL is unpredictable and you need sql_mode=only_full_group_by:
GROUP BY lname ORDER BY showing wrong results;
Which is the least expensive aggregate function in the absence of ANY() (see comments in accepted answer).
Ora...
How do I create a crontab through a script
...moving existing crontab entries and also I needed to use a different user (root) so I used the following to maintain the existing entries: echo -e "$(sudo crontab -u root -l)\n* * * * * echo hello > /home/danny/temp.log 2>&1" | sudo crontab -u root - Hopefully this helps someone
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How do you write multiline strings in Go?
...DanieleD That's a slight nonsequitur, but which dialect? Presumably mainly MySQL? stackoverflow.com/a/10574031 Note that by extension of the same argument, it's a pain for embedding markdown, or shell scripts (if you opt to use backtick in place of $(abcd)).
– Ivan Vučica
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Add a reference column migration in Rails 4
... Active Record only supports single column foreign keys and currently only mysql, mysql2 and PostgreSQL adapters are supported. Don't try this with other adapters like sqlite3, etc. Refer to Rails Guides: Foreign Keys for your reference.
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Where does npm install packages?
...y. It will then typically be found in /usr/local/lib/node_modules (Use npm root -g to check where.)
npm install pm2 - pm2 will be installed locally. It will then typically be found in the local directory in /node_modules
sh...