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Cannot delete or update a parent row: a foreign key constraint fails
... (`advertiser_id`)
REFERENCES `jobs` (`advertiser_id`);
...is actually the opposite to what it should be. As it is, it means that you'd have to have a record in the jobs table before the advertisers. So you need to use:
ALTER TABLE `jobs`
ADD CONSTRAINT `advertisers_ibfk_1` FOREIGN KEY...
When do I use the PHP constant “PHP_EOL”?
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@Andre: How about anyone that writes apps to be installed, used and deployed by others? Are you suggesting these should all limit their "supported platforms" to *nix?
– Cylindric
Mar 4 '11 at 10:52
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Getting the object's property name
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More specifically, Object.keys(obj) returns an array of property names, i.e. keys, belonging to the passed in obj.
– a learner has no name
Mar 26 '16 at 12:43
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How can a LEFT OUTER JOIN return more records than exist in the left table?
I have a very basic LEFT OUTER JOIN to return all results from the left table and some additional information from a much bigger table. The left table contains 4935 records yet when I LEFT OUTER JOIN it to an additional table the record count is significantly larger.
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Hadoop “Unable to load native-hadoop library for your platform” warning
...e native Hadoop library $HADOOP_HOME/lib/native/libhadoop.so.1.0.0 was actually compiled on 32 bit.
Anyway, it's just a warning, and won't impact Hadoop's functionalities.
Here is the way if you do want to eliminate this warning, download the source code of Hadoop and recompile libhadoop.so.1.0....
Project structure for Google App Engine
.... However, as it has grown, and features have been added, it has gotten really difficult to keep things organized - mainly due to the fact that this is my first python project, and I didn't know anything about it until I started working.
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Rails check if yield :area is defined in content_for
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not really necessary to create a helper method:
<% if @content_for_sidebar %>
<div id="sidebar">
<%= yield :sidebar %>
</div>
<% end %>
then of course in your view:
<% content_for :sideb...
Where are static variables stored in C and C++?
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@Don Neufeld: your answer does not answer the question at all. I do not understand why it is accepted. Because the both the 'foo' and 'bar' are non-0 initialized. The question is where to place two static/global variable with the same name in .bss or .data
– lu...
How to round a number to significant figures in Python
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round_sig = lambda f,p: float(('%.' + str(p) + 'e') % f) allows you to adjust the number of significant digits!
– denizb
Aug 6 '17 at 22:43
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How can I access “static” class variables within class methods in Python?
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As with all good examples, you've simplified what you're actually trying to do. This is good, but it is worth noting that python has a lot of flexibility when it comes to class versus instance variables. The same can be said of meth...