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PadLeft function in T-SQL
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STR() only works on numbers (or numbers in string fields). This code breaks if you are using it on a varchar field that you assume to have a number but one of the records has bad (non-numeric) data. The RIGHT() function won't break in this case.
–...
What are the differences between a clustered and a non-clustered index?
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Clustered indexes physically order the data on the disk. This means no extra data is needed for the index, but there can be only one clustered index (obviously). Accessing data using a clustered index is fastest.
All other indexes must be non-clustered. A non-clustered index has a duplicate of ...
What is a WeakHashMap and when to use it? [duplicate]
...is good to implement canonical maps. Lets say you want to associate
some extra information to an object that you have a strong reference
to. You put an entry in a WeakHashMap with the object as the key, and
the extra information as the map value. Then, as long as you keep a
strong reference ...
Converting HTML string into DOM elements? [duplicate]
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You can use a DOMParser, like so:
var xmlString = "<div id='foo'><a href='#'>Link</a><span></span></div>";
var doc = new DOMParser().parseFromString(xmlString, "text/xml");
console.log(doc.firstChild.innerHTML); // => <a h...
What exactly is nullptr?
...ranteed to be 0. It can be 0L, in which case a call to void f(int); void f(char *); will be ambiguous. nullptr will always favor the pointer version, and never call the int one. Also note that nullptr is convertible to bool (the draft says that at 4.12).
– Johannes Schaub - lit...
Using Enums while parsing JSON with GSON
...gson.JsonParseException;
public class GsonFoo
{
public static void main(String[] args) throws Exception
{
GsonBuilder gsonBuilder = new GsonBuilder();
gsonBuilder.registerTypeAdapter(AttributeScope.class, new AttributeScopeDeserializer());
Gson gson = gsonBuilder.create();
Trun...
Convert a list to a dictionary in Python
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You can also do it like this (string to list conversion here, then conversion to a dictionary)
string_list = """
Hello World
Goodbye Night
Great Day
Final Sunset
""".split()
string_list = dict(zip(string_list[::2],string_list...
python pandas: apply a function with arguments to a series
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Note: If you are passing a single string argument, for example 'abc', then args=('abc') will be evaluated as three arguments ('a', 'b', 'c'). To avoid this, you must pass a tuple containing the string, and to do that, include a trailing comma: args=('abc',)
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Is Java's assertEquals method reliable?
I know that == has some issues when comparing two Strings . It seems that String.equals() is a better approach. Well, I'm doing JUnit testing and my inclination is to use assertEquals(str1, str2) . Is this a reliable way to assert two Strings contain the same content? I would use assertTr...
Pandas conditional creation of a series/dataframe column
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Update: On 100,000,000 rows, 52 string values, .apply() takes 47 seconds, versus only 5.91 seconds for .map().
– AMC
Feb 10 at 2:18
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