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Why does Convert.ToString(null) return a different value if you cast null?
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There are 2 overloads of ToString that come into play here
Convert.ToString(object o);
Convert.ToString(string s);
The C# compiler essentially tries to pick the most specific overload which will work with the input. A null value is convertible to any reference type. In this case ...
How do I convert from BLOB to TEXT in MySQL?
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That's unnecessary. Just use SELECT CONVERT(column USING utf8) FROM..... instead of just SELECT column FROM...
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Is there a concise way to iterate over a stream with indices in Java 8?
... class CollectionUtils {
private CollectionUtils() { }
/**
* Converts an {@link java.util.Iterator} to {@link java.util.stream.Stream}.
*/
public static <T> Stream<T> iterate(Iterator<? extends T> iterator) {
int characteristics = Spliterator.ORDERED ...
Why is there no SortedList in Java?
...the comments) you need to poll() the queue until empty.
Note that you can convert a list to a priority queue via the constructor that takes any collection:
List<String> strings = new ArrayList<String>()
strings.add("lol");
strings.add("cat");
PriorityQueue<String> sortedStrings ...
How do I make calls to a REST api using C#?
...orization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", Convert.ToBase64String(cred));
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
System.Net.Http.HttpContent content = new Strin...
Using a .php file to generate a MySQL dump
...qldump and see the password).
//create a temporary file
$file = tempnam(sys_get_temp_dir(), 'mysqldump');
//store the configuration options
file_put_contents($file, "[mysqldump]
user={$user}
password=\"{$password}\"");
//execute the command and output the result
passthru("mysqldump --defaults-f...
Why is “while ( !feof (file) )” always wrong?
...he result we must use is the return value of scanf, the number of elements converted.
C++, iostreams formatted extraction:
for (int n; std::cin >> n; ) {
consume(n);
}
The result we must use is std::cin itself, which can be evaluated in a boolean context and tells us whether the ...
Convert data.frame columns from factors to characters
... data.frame(lapply(bob, as.character), stringsAsFactors=FALSE)
This will convert all variables to class "character", if you want to only convert factors, see Marek's solution below.
As @hadley points out, the following is more concise.
bob[] <- lapply(bob, as.character)
In both cases, lapp...
How to return only the Date from a SQL Server DateTime datatype
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On SQL Server 2008 and higher, you should CONVERT to date:
SELECT CONVERT(date, getdate())
On older versions, you can do the following:
SELECT DATEADD(dd, 0, DATEDIFF(dd, 0, @your_date))
for example
SELECT DATEADD(dd, 0, DATEDIFF(dd, 0, GETDATE()))
gives me ...
Java's Virtual Machine and CLR
...in run-time environments: bytecode compilation and dynamic compilation. It converts code at runtime prior to executing it natively, for example bytecode into native machine code. The performance improvement over interpreters originates from caching the results of translating blocks of code, and not ...