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SQL “select where not in subquery” returns no results
...emantically the same.
When it is nullable, NOT IN is different, since IN (and, therefore, NOT IN) return NULL when a value does not match anything in a list containing a NULL.
This may be confusing but may become more obvious if we recall the alternate syntax for this:
common_id = ANY
(
SELECT c...
Intermittent log4net RollingFileAppender locked file issue
We are seeing an intermittent issue on development and production machines whereby our log files are not getting logged to.
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Entity Framework: table without primary key
...t to. The number of confusing bugs that could be introduced is staggering and scary, not to mention the fact that your performance will likely go down the tubes.
Don't work around this. Fix your data model.
EDIT: I've seen that a number of people are downvoting this question. That's fine, I sup...
How to redirect to a 404 in Rails?
...
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way.
This does two things better:
1) It uses Rails' built in rescue_from handler to render the 404 page, and
2) it interrupts the executi...
Looping through a hash, or using an array in PowerShell
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Christian's answer works well and shows how you can loop through each hash table item using the GetEnumerator method. You can also loop through using the keys property. Here is an example how:
$hash = @{
a = 1
b = 2
c = 3
}
$hash.Keys | % { "...
Xcode stuck on Indexing
...xing". I can't Build the project anymore. If I try to build, Xcode freezes and I have to force quit. This happens only with this project.
...
Highlight bash/shell code in markdown
How to highlight the bash/shell commands in markdown files?
7 Answers
7
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How do I include a pipe | in my linux find -exec command?
...f interpreting the pipe symbol as an instruction to run multiple processes and pipe the output of one process into the input of another process is the responsibility of the shell (/bin/sh or equivalent).
In your example you can either choose to use your top level shell to perform the piping like s...
Can I access constants in settings.py from templates in Django?
...quently-used settings constants to the template such as settings.MEDIA_URL and some of the language settings if you use django's built in generic views or pass in a context instance keyword argument in the render_to_response shortcut function. Here's an example of each case:
from django.shortcuts ...
“Unresolved inclusion” error with Eclipse CDT for C standard library headers
I set up CDT for eclipse and wrote a simple hello world C program:
14 Answers
14
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