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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 you find the row count for all your tables in Postgres
...he outer xpath() will then extract the count information from that xml and convert it to a number
The derived table is not really necessary, but makes the xpath() a bit easier to understand - otherwise the whole query_to_xml() would need to be passed to the xpath() function.
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Get nested JSON object with GSON using retrofit
...= new Retrofit.Builder()
.baseUrl(url)
.addConverterFactory(GsonConverterFactory.create(gson))
.build();
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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 ...
Script entire database SQL-Server
...werShell. Otherwise start looking at RedGate tools, or Visual Studio Team Systems with Database Developer.
– Chris Brandsma
Nov 11 '10 at 16:30
7
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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 ...
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...
How to export and import environment variables in windows?
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You can use RegEdit to export the following two keys:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment
HKEY_CURRENT_USER\Environment
The first set are system/global environment variables; the second set are user-level variables. Edit as needed and then import the...