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Is it fine to have foreign key as primary key?
...reign keys are almost always "Allow Duplicates," which would make them unsuitable as Primary Keys.
Instead, find a field that uniquely identifies each record in the table, or add a new field (either an auto-incrementing integer or a GUID) to act as the primary key.
The only exception to this are t...
PowerShell says “execution of scripts is disabled on this system.”
...ExecutionPolicy Cmdlet.
When you are done, you can set the policy back to its default value with:
Set-ExecutionPolicy Restricted
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Difference between validate(), revalidate() and invalidate() in Swing GUI
...s invalid. Means the content is somehow wrong and must be re-laid out. But it's just a kind of mark/flag. It's possible that multiple invalid containers must be refreshed later.
validate() performs relayout. It means invalid content is asked for all the sizes and all the subcomponents' sizes are se...
Chrome hangs after certain amount of data transfered - waiting for available socket
...
Looks like you are hitting the limit on connections per server. I see you are loading a lot of static files and my advice is to separate them on subdomains and serve them directly with Nginx for example.
Create a subdomain called img.yoursite...
Python (and Python C API): __new__ versus __init__
...m about to ask seems to be a duplicate of Python's use of __new__ and __init__? , but regardless, it's still unclear to me exactly what the practical difference between __new__ and __init__ is.
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Java: How to set Precision for double value? [duplicate]
I was working with numbers recently and I had a situation where I want to set the precision of a double value say to 6 digits or 4 digits, depending on the value stored in the database.
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Android ListView Divider
...ed, which rounds to 0. On some devices, that translates to 2-3 pixels, and it usually looks ugly or sloppy
For dividers, 1px is the correct height if you want a 1 pixel divider and is one of the exceptions for the "everything should be dip" rule. It'll be 1 pixel on all screens. Plus, 1px usually l...
Python List vs. Array - when to use?
If you are creating a 1d array, you can implement it as a List, or else use the 'array' module in the standard library. I have always used Lists for 1d arrays.
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Guaranteed lifetime of temporary in C++?
...vide a guarantee for the lifetime of a temporary variable that is created within a function call but not used as a parameter? Here's an example class:
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Haml: Control whitespace around text
...ucceed ',' do
= link_to 'link somewhere', 'http://example.com'
- if @condition
then render this half of the sentence if a condition is met
Produces:
I will first
<a href="http://example.com">link somewhere</a>,
then render this half of the sentence if a condition is met
...