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How do I get SUM function in MySQL to return '0' if no values are found?
...nformation:
Given three tables (one with all numbers, one with all nulls, and one with a mixture):
SQL Fiddle
MySQL 5.5.32 Schema Setup:
CREATE TABLE foo
(
id INT NOT NULL AUTO_INCREMENT PRIMARY KEY,
val INT
);
INSERT INTO foo (val) VALUES
(null),(1),(null),(2),(null),(3),(null),(4),(n...
Get pandas.read_csv to read empty values as empty string instead of nan
I'm using the pandas library to read in some CSV data. In my data, certain columns contain strings. The string "nan" is a possible value, as is an empty string. I managed to get pandas to read "nan" as a string, but I can't figure out how to get it not to read an empty value as NaN. Here's sam...
HttpServletRequest - how to obtain the referring URL?
...ng.
You, however, need to realize that this is a client-controlled value and can thus be spoofed to something entirely different or even removed. Thus, whatever value it returns, you should not use it for any critical business processes in the backend, but only for presentation control (e.g. hidin...
using gitignore to ignore (but not delete) files
...f .gitignore, you can update local git repository by running following command:
git update-index --assume-unchanged <file>
In this case a file is being tracked in the origin repo. You can modify it in your local repo and git will never mark it as changed. Read more at:
http://blog.pagebak...
How to get the original value of an attribute in Rails
...ibute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should append _before_last_save
Something like:
before_save object
do_something_with object.name_...
How to undo another user’s checkout in TFS?
...
There are at least 2 different ways to do this:
Command Line
There is a command-line utility called Tf.exe that comes with Team Explorer. Find the documentation here. It can be accessed by launching a Visual Studio Command Prompt window. The syntax of the command is:
tf undo...
Why does LayoutInflater ignore the layout_width and layout_height layout parameters I've specified?
I've had severe trouble getting LayoutInflater to work as expected, and so did other people: How to use layoutinflator to add views at runtime? .
...
How does Chrome's “Request Desktop Site” option work?
...ader in the request.
Here are the User-Agent headers sent by Chrome on my Android device:
Mozilla/5.0 (Linux; Android 4.0.4; Galaxy Nexus Build/IMM76K) AppleWebKit/535.19 (KHTML, like Gecko) Chrome/18.0.1025.166 Mobile Safari/535.19
Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/535.19 (KHTML, like ...
SCOPE_IDENTITY() for GUIDs?
...key mentions, you should be using NewSequentialID() to generate your GUIDs and not NewID().
– Rob Garrison
Oct 2 '09 at 16:32
1
...
GROUP_CONCAT ORDER BY
... postfix: "",
imageUploader: {
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