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MySQL: What's the difference between float and double?

...00002 | 1.6900000000 | This is using MySQL 6.7 Query: SELECT float_1 + float_2 as 'float add', double_1 + double_2 as 'double add', decimal_1 + decimal_2 as 'decimal add', float_1 * float_2 as 'float multiply', double_1 * double_2 as 'double multiply', decimal_1 * decim...
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What breaking changes are introduced in C++11?

...nity, whereas C++0x always rounds the result toward 0. (admittedly not really a compatibility problem for most people). Valid C++ 2003 code that uses the keyword auto as a storage class specifier may be invalid in C++0x. Narrowing conversions cause incompatibilities with C++03. For ex...
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Dictionary returning a default value if the key does not exist [duplicate]

...Value(key, out value); and just ignore the return value. However, that really will just return default(TValue), not some custom default value (nor, more usefully, the result of executing a delegate). There's nothing more powerful built into the framework. I would suggest two extension methods: pu...
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When to use inline function and when not to use it?

...at inline is a hint or request to compiler and its used to avoid function call overheads. 14 Answers ...
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SQL Server database backup restore on lower version

...R2 or restore the backup you have on a SQL Server 2008 R2 instance, export all the data and import it on a SQL Server 2008 database. share | improve this answer | follow ...
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Django set field value after a form is initialized

...value after the form was submitted, you can use something like: if form.is_valid(): form.cleaned_data['Email'] = GetEmailString() Check the referenced docs above for more on using cleaned_data share | ...
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How can I match a string with a regex in Bash?

...ching in the second example. Inside [[ ]], the * is not expanded as it usually is, to match filenames in the current directory that match a pattern.Your example works, but it's really easy to over-generalize and mistakenly believe that * means to match anything in any context. It only works like t...
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Should I use 'has_key()' or 'in' on Python dicts?

... in is definitely more pythonic. In fact has_key() was removed in Python 3.x. share | improve this answer | follow | ...
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Date vs DateTime

... Unfortunately, not in the .Net BCL. Dates are usually represented as a DateTime object with the time set to midnight. As you can guess, this means that you have all the attendant timezone issues around it, even though for a Date object you'd want absolutely no timezone han...
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How do I implement a callback in PHP?

How are callbacks written in PHP? 9 Answers 9 ...