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MySQL: Set user variable from result of query
...
Yes, but you need to move the variable assignment into the query:
SET @user := 123456;
SELECT @group := `group` FROM user WHERE user = @user;
SELECT * FROM user WHERE `group` = @group;
Test case:
CREATE TABLE user (`user` int, `group` int);
INSERT INTO user VALUES (12345...
Setting a timeout for socket operations
...
Use the Socket() constructor, and connect(SocketAddress endpoint, int timeout) method instead.
In your case it would look something like:
Socket socket = new Socket();
socket.connect(new InetSocketAddress(ipAddress, port), 1000);
Quoting from the documentation
connect
public...
Using Excel OleDb to get sheet names IN SHEET ORDER
...ced through the comments that there are a lot of concerns about using the Interop classes to retrieve the sheet names. Therefore here is an example using OLEDB to retrieve them:
/// <summary>
/// This method retrieves the excel sheet names from
/// an excel workbook.
/// </summary>
//...
Using isKindOfClass with Swift
I'm trying to pick up a bit of Swift lang and I'm wondering how to convert the following Objective-C into Swift:
5 Answers
...
deleting rows in numpy array
... [ 0.78008333, 0.5938125, 0.481, 0.39883333, 0.]])
>>> print arr[arr.all(1)]
array([[ 0.96488889, 0.73641667, 0.67521429, 0.592875 , 0.53172222]])
By the way, this method is much, much faster than the masked array method for large matrices. For a 2048 x 5 matrix, this method...
Is there a way to make ellipsize=“marquee” always scroll?
...iew all focused.
@Override
protected void onFocusChanged(boolean focused, int direction, Rect previouslyFocusedRect) {
if(focused)
super.onFocusChanged(focused, direction, previouslyFocusedRect);
}
@Override
public void onWindowFocusChanged(boolean focused) {
if(focused)
su...
Can't specify the 'async' modifier on the 'Main' method of a console app
...onous console programs in particular. Here's some background info from the intro post:
If "await" sees that the awaitable has not completed, then it acts asynchronously. It tells the awaitable to run the remainder of the method when it completes, and then returns from the async method. Await will a...
What strategies and tools are useful for finding memory leaks in .NET?
...ul about the number of objects that we inflated in memory. In the end, we converted all of our data objects over to an "inflate on-demand" (just before a field is requested) in order to reduce memory overhead and increase performance.
EDIT: Here's a further explanation of what I mean by "inflate o...
How to use permission_required decorators on django class-based views
...ort method_decorator
def class_view_decorator(function_decorator):
"""Convert a function based decorator into a class based decorator usable
on class based Views.
Can't subclass the `View` as it breaks inheritance (super in particular),
so we monkey-patch instead.
"""
def ...
Does JSON syntax allow duplicate keys in an object?
...<a>x</a>
<a>y</a>
</object>
When this is converted into JSON, you get the following:
{
"object": {
"a": [
"x",
"y"
]
}
}
A natural mapping from a language that handles what you might call duplicate keys to another, can serve as a potential...