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LEFT OUTER joins in Rails 3
...OUTER JOIN users ON users.id = posts.user_id").
joins(:blog).select
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JavaScript get clipboard data on paste event (Cross browser)
...vent using a keypress event handler
In that handler, save the current user selection, add a textarea element off-screen (say at left -1000px) to the document, turn designMode off and call focus() on the textarea, thus moving the caret and effectively redirecting the paste
Set a very brief timer (say...
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...
Map and Reduce in .NET
...ons. C# 3.5 and Linq already has it albeit under different names.
Map is Select:
Enumerable.Range(1, 10).Select(x => x + 2);
Reduce is Aggregate:
Enumerable.Range(1, 10).Aggregate(0, (acc, x) => acc + x);
Filter is Where:
Enumerable.Range(1, 10).Where(x => x % 2 == 0);
https://www...
Select between two dates with Django
I am looking to make a query that selects between dates with Django.
4 Answers
4
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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...
iPhone app signing: A valid signing identity matching this profile could not be found in your keycha
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Open Xcode. Click WINDOW > ORGANIZER. Then click the Devices tab and select "Provisioning Profiles" on the left.
That should bring up your provisioning profiles. Highlight one by one (if more than 1), right click and delete profile. Yes, just do it! Delete them all! (I kept making a new one a...
Is it possible to apply CSS to half of a character?
.../
overflow: hidden;
pointer-events: none; /* so the base char is selectable by mouse */
color: #f00; /* for demo purposes */
text-shadow: 2px -2px 0px #af0; /* for demo purposes */
}
.halfStyle:after { /* creates the right part */
display: block;
direction: rtl; /* ...
Uniq by object attribute in Ruby
What's the most elegant way to select out objects in an array that are unique with respect to one or more attributes?
14 An...
How do I get the “id” after INSERT into MySQL database with Python?
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Does not works with duplicated records using insert, select and where.
– e-info128
Oct 27 '18 at 19:20
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