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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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Why are joins bad when considering scalability?
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...except in MySQL, which seems to have performance problems with large numbers of joins regardless of how your indexes look. Or at least it has in the past.
– Powerlord
Apr 12 '10 at 17:53
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How is null + true a string?
...for the operation operator op(x, y) is determined. The set consists of the union of the candidate operators provided by X and the candidate operators provided by Y, each determined using the rules of §7.3.5. If X and Y are the same type, or if X and Y are derived from a common base type, then share...
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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How to insert element into arrays at specific position?
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array_slice() can be used to extract parts of the array, and the union array operator (+) can recombine the parts.
$res = array_slice($array, 0, 3, true) +
array("my_key" => "my_value") +
array_slice($array, 3, count($array)-3, true);
This example:
$array = array(
'zero' ...
Unpivot with column name
... VALUES, when not available, can be replaced by a subquery with SELECT ... UNION ... SELECT ... Wondering about the performance of that CROSS JOIN though...
– Cristi S.
Oct 16 '18 at 20:39
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How to install python modules without root access?
...asy_install to install python packages in your home directory even without root access. There's a standard way to do this using site.USER_BASE which defaults to something like $HOME/.local or $HOME/Library/Python/2.7/bin and is included by default on the PYTHONPATH
To do this, create a .pydistutils...
How to use count and group by at the same select statement
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needs alias otherwise wouldnt work in mysql. select count(*) from( ) agr
– amas
Jan 9 '14 at 6:54
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How can I detect if the user is on localhost in PHP?
...n.
I think what you remember with PHPMyAdmin is something different: Many MySQL Servers are configured so that they can only be accessed from localhost for security reasons.
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What's the easy way to auto create non existing dir in ansible
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Right now, this is the only way
- name: Ensures {{project_root}}/conf dir exists
file: path={{project_root}}/conf state=directory
- name: Copy file
template:
src: code.conf.j2
dest: "{{project_root}}/conf/code.conf"
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