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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...
Center Align on a Absolutely Positioned Div
...t. This is awesome! Could you explain how it works? Edit: Did some hunting and it seems like the left: 50% moves the div's left location to the center, which isn't really center. But the translateX shifts it back 50% of the content's width
– Aziz Javed
Nov 10 '...
How to use ternary operator in razor (specifically on HTML attributes)?
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Here's a handy reference to Razor syntax: C# Razor Syntax Quick Reference
– Ryan Lundy
Jun 24 '11 at 15:24
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What does it mean to start a PHP function with an ampersand?
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An ampersand before a function name means the function will return a reference to a variable instead of the value.
Returning by reference is useful when
you want to use a function to find to
which variable a reference should b...
Can you use an alias in the WHERE clause in mysql?
...e performance implications since HAVING executes after the data is fetched and WHERE executes before.
– StockB
Feb 15 '17 at 19:16
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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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I needed an answer to this very question and started googling for the docs. Instead of the Postgres documentation, I ran into this topic at StackOverflow. So although it's a good think to reference the official docs, it's also very good to give the answer for future...
How to do ssh with a timeout in a script?
... is taking an infinite time to run, I want to come out of that ssh session and continue other lines in my sh script.
6 Answ...
Trying to fire the onload event on script tag
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can you help me understand why the ordering is important?
– chovy
Apr 26 '13 at 8:19
12
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SQLite: How do I save the result of a query as a CSV file?
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From here and d5e5's comment:
You'll have to switch the output to csv-mode and switch to file output.
sqlite> .mode csv
sqlite> .output test.csv
sqlite> select * from tbl1;
sqlite> .output stdout
...