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The differences between .build, .create, and .create! and when should they be used?
So I've been seeing people using .build , .create , and .create! within their controllers more and more lately. What's the difference from just using .new and passing the param'd object and then .save ? Are there pros and cons? Does using these other methods offer benefits?
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How to check if command line tools is installed
...as it appears in the Applications directory.
There are also the xcodebuild and xcode-select files in /usr/bin
I need to know if the command line tools is installed.
Is there a command for it?
What can I do to see if XCode CLT is installed and if yes to find the version installed?
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Importance of varchar length in MySQL table
...serted dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessary?
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How to exit from Python without traceback?
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You are presumably encountering an exception and the program is exiting because of this (with a traceback). The first thing to do therefore is to catch that exception, before exiting cleanly (maybe with a message, example given).
Try something like this in your main r...
How do detect Android Tablets in general. Useragent?
...sing a Motorola Zoom to try our tablet site testing.
The issue is that the Android Useragent is a general Useragent and there is no difference between tablet Android and mobile Android. I don't want to just target a specific device like the Xoom Useragent since Android will most likely be on multip...
Should switch statements always contain a default clause?
...pe! based on the language,
// there should probably be some error-handling
// here, maybe an exception
}
2. To handle 'default' actions, where the cases are for special behavior.
You see this a LOT in menu-driven programs and bash shell scripts. You might also see this when a vari...
How to fetch the row count for all tables in a SQL SERVER database [duplicate]
... table_name varchar(255),
row_count int
)
EXEC sp_MSForEachTable @command1='INSERT #counts (table_name, row_count) SELECT ''?'', COUNT(*) FROM ?'
SELECT table_name, row_count FROM #counts ORDER BY table_name, row_count DESC
DROP TABLE #counts
The output will be a list of tables and their row ...
Where is the “Fold” LINQ Extension Method?
... prod * next);
See MSDN for more information. It lets you specify a seed and then an expression to calculate successive values.
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Counting the number of elements with the values of x in a vector
... x creates a logical vector which is TRUE at every location that x occurs, and when suming, the logical vector is coerced to numeric which converts TRUE to 1 and FALSE to 0.
However, note that for floating point numbers it's better to use something like: sum(abs(numbers - x) < 1e-6).
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Adjusting the Xcode iPhone simulator scale and size [duplicate]
...5 in Xcode, be the actual size of the iPhone 5. I'm getting a huge display and things seemed to be scaled.
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