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Rails: Why does find(id) raise an exception in rails? [duplicate]
...ctiveRecord, the default behaviour is to return nil or false for failures, and leave the exception control flow to methods ending in a bang (#save!).
– Marten Veldthuis
Aug 12 '11 at 8:07
...
How do I check OS with a preprocessor directive?
...them, with links to where they're found:
Windows
_WIN32 Both 32 bit and 64 bit
_WIN64 64 bit only
Unix (Linux, *BSD, Mac OS X)
See this related question on some of the pitfalls of using this check.
unix
__unix
__unix__
Mac OS X
__APPLE__
__MACH__
Both are defined; checking for eith...
UDP vs TCP, how much faster is it? [closed]
...
UDP is faster than TCP, and the simple reason is because its non-existent acknowledge packet (ACK) that permits a continuous packet stream, instead of TCP that acknowledges a set of packets, calculated by using the TCP window size and round-trip tim...
Has reCaptcha been cracked / hacked / OCR'd / defeated / broken? [closed]
...re relate to the ineffectiveness of the concept of CAPTCHA, in principle - and while I very much agree with them, in fact gave a talk at OWASP a few months ago explaining just that - the question is very specific, so I will provide for a demonstration.
But first, I will reiterate that demonstration ...
How to create a temporary directory/folder in Java?
Is there a standard and reliable way of creating a temporary directory inside a Java application? There's an entry in Java's issue database , which has a bit of code in the comments, but I wonder if there is a standard solution to be found in one of the usual libraries (Apache Commons etc.) ?
...
More elegant way of declaring multiple variables at the same time
...called function. This is certainly a reliable way to create dictionaries, and people seem to be at least accepting of this idiom, but I suspect that some may consider it Unpythonic. </disclaimer>
Yet another approach, which is likely the most intuitive if you will be using this pattern fr...
Merge / convert multiple PDF files into one PDF
...er to provide out.pdf, or else it will overwrite the last file in your command, sigh.
– mlissner
Oct 19 '13 at 22:20
10
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Oracle TNS names not showing when adding new connection to SQL Developer
...RACLE\ORACLE_HOME
To see which one SQL Developer is using, issue the command show tns in the worksheet
If your tnsnames.ora file is not getting recognized, use the following procedure:
Define an environmental variable called TNS_ADMIN to point to the folder that contains your tnsnames.ora file....
How do I convert a String to an int in Java?
...s function can throw a NumberFormatException, which of course you have to handle:
int foo;
try {
foo = Integer.parseInt(myString);
}
catch (NumberFormatException e)
{
foo = 0;
}
(This treatment defaults a malformed number to 0, but you can do something else if you like.)
Alternatively, you ca...
How can I wait for set of asynchronous callback functions?
...h your code, so I'll make up a scenario. Let's say you have 10 ajax calls and you want to accumulate the results from those 10 ajax calls and then when they have all completed you want to do something. You can do it like this by accumulating the data in an array and keeping track of when the last ...