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OrderBy descending in Lambda expression?
I know in normal Linq grammar, orderby xxx descending is very easy, but how do I do this in Lambda expression?
6 Answers
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Are PDO prepared statements sufficient to prevent SQL injection?
...rt off by showing the attack...
$pdo->query('SET NAMES gbk');
$var = "\xbf\x27 OR 1=1 /*";
$query = 'SELECT * FROM test WHERE name = ? LIMIT 1';
$stmt = $pdo->prepare($query);
$stmt->execute(array($var));
In certain circumstances, that will return more than 1 row. Let's dissect what's go...
How expensive is RTTI?
... RTTI, but how big is it? Everywhere I've looked just says that "RTTI is expensive," but none of them actually give any benchmarks or quantitative data reguarding memory, processor time, or speed.
...
How does interfaces with construct signatures work?
...in interfaces are not implementable in classes; they're only for defining existing JS APIs that define a 'new'-able function. Here's an example involving interfaces new signatures that does work:
interface ComesFromString {
name: string;
}
interface StringConstructable {
new(n: string): Co...
Why is SELECT * considered harmful?
...ially true when someone adds new columns to underlying tables that didn't exist and weren't needed when the original consumers coded their data access.
Indexing issues. Consider a scenario where you want to tune a query to a high level of performance. If you were to use *, and it returned more col...
pandas GroupBy columns with NaN (missing) values
...Missing Data section of the docs:
NA groups in GroupBy are automatically excluded. This behavior is consistent with R, for example.
One workaround is to use a placeholder before doing the groupby (e.g. -1):
In [11]: df.fillna(-1)
Out[11]:
a b
0 1 4
1 2 -1
2 3 6
In [12]: df.fillna(-1...
Is D a credible alternative to Java and C++? [closed]
...o support in any modern IDEs (there are plugins for both Visual Studio and Xamarin Studio/MonoDevelop), limited dynamic/shared library support, and few bindings to other languages, D is simply not an option today.
If you like what you see of D, by all means, learn it - it shouldn't take long if you...
String formatting: % vs. .format vs. string literal
...on 2.6 introduced the str.format() method with a slightly different syntax from the existing % operator. Which is better and for what situations?
...
GetType() can lie?
...cessfully lied, right?
Well, yes and no... Consider that using this as an exploit would mean using your BadFoo instance as an argument to a method somewhere, that expects likely an object or a common base type for a hierarchy of objects. Something like this:
public void CheckIfInt(object ob)
{
...