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How do I get the MAX row with a GROUP BY in LINQ query?
...t by t.SerialNumber
into g
select new
{
SerialNumber = g.Key,
uid = (from t2 in g select t2.uid).Max()
};
}
...
What does the “>” (greater-than sign) CSS selector mean?
...etimes mistakenly called the direct descendant combinator.1
That means the selector div > p.some_class only selects paragraphs of .some_class that are nested directly inside a div, and not any paragraphs that are nested further within.
An illustration:
div > p.some_class {
background:...
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
... 0.0 NaN 0.0
3 0.0 1.0 2.0 3.0
4 NaN 0.0 NaN NaN
If you want to select the rows that have two or more columns with null value, you run the following:
>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
0 1 2 3
1 0.0 NaN 0...
How do I pass the value (not the reference) of a JS variable to a function? [duplicate]
...sults[i];
google.maps.event.addListener(marker, 'click', () => change_selection(i));
}
In older browsers, you need to create a separate scope that saves the variable in its current state by passing it as a function parameter:
for (var i = 0; i < results.length; i++) {
(function (i) {...
How to remove a Gitlab project?
...
Go to the project page
Select "Settings"
Select the "General" section (you must be in the repository you want to delete to delete it)
If you have enough rights, then at the bottom of the page will be a button for "Advanced settings" (i.e. project s...
How do I set up NSZombieEnabled in Xcode 4?
...
⌥⌘R
(or click Menubar > Product > Scheme > Edit Scheme)
select the "Diagnostics" tab and click "Enable Zombie Objects":
This turns released objects into NSZombie instances that print console warnings when used again. This is a debugging aid that increases memory use (no objec...
What are the uses for Cross Join?
...ly, like size and color information for a particular article of clothing:
select
size,
color
from
sizes CROSS JOIN colors
Maybe you want a table that contains a row for every minute in the day, and you want to use it to verify that a procedure has executed each minute, so you might c...
Is there a way to automatically generate getters and setters in Eclipse?
...nu (i.e. right click) in the source code window of the desired class. Then select the Source submenu; from that menu selecting Generate Getters and Setters... will cause a wizard window to appear.
Source -> Generate Getters and Setters...
Select the variables you wish to create getters and sett...
JSON encode MySQL results
...
$sth = mysqli_query($conn, "SELECT ...");
$rows = array();
while($r = mysqli_fetch_assoc($sth)) {
$rows[] = $r;
}
print json_encode($rows);
The function json_encode needs PHP >= 5.2 and the php-json package - as mentioned here
NOTE: mysql is dep...
How to create unit tests easily in eclipse [closed]
I want to create unit tests easily by just selecting method. Is there a tool in eclipse that does that. It should support templates. I should be able to create positive test as well as negative tests.
...