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Check if page gets reloaded or refreshed in JavaScript
...ome had recently change this behavior. When user click current address bar and hit enter, the value of performance.navigation.type will be 1 which should be 0. I tested in Version 56. Not sure why.
– Jackwin tung
Feb 19 '17 at 9:28
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What are the differences and similarities between ffmpeg, libav, and avconv?
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Confusing messages
These messages are rather misleading and understandably a source of confusion. Older Ubuntu versions used Libav which is a fork of the FFmpeg project. FFmpeg returned in Ubuntu 15.04 "Vivid Vervet".
The fork was basically a non-amicable result of conflicting pe...
CentOS 64 bit bad ELF interpreter
...it version, I'm trying to install a 32-bit application on a 64-bit machine and got this error:
8 Answers
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Iterator Loop vs index loop [duplicate]
I'm reviewing my knowledge on C++ and I've stumbled upon iterators. One thing I want to know is what makes them so special and I want to know why this:
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Manually adding a Userscript to Google Chrome
...ey extension.
This will allow you to easily install Greasemonkey scripts, and to easily manage them. Also it makes it easier to install userscripts directly from sites like OpenUserJS, MonkeyGuts, etc.
Finally, it unlocks most all of the GM functionality that you don't get by installing a GM scri...
Why is it impossible to build a compiler that can determine if a C++ function will change the value
...er any given program will terminate. This is known as the halting problem, and it's one of those things that's not computable.
To be clear, you can write a compiler that can determine that a function does change the variable in some cases, but you can't write one that reliably tells you that the fu...
Why compile Python code?
...d you compile a Python script? You can run them directly from the .py file and it works fine, so is there a performance advantage or something?
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What is the formal difference in Scala between braces and parentheses, and when should they be used?
...rmal difference between passing arguments to functions in parentheses () and in braces {} ?
9 Answers
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Insert, on duplicate update in PostgreSQL?
...mple 38-2. Exceptions with UPDATE/INSERT
This example uses exception handling to perform either UPDATE or INSERT, as appropriate:
CREATE TABLE db (a INT PRIMARY KEY, b TEXT);
CREATE FUNCTION merge_db(key INT, data TEXT) RETURNS VOID AS
$$
BEGIN
LOOP
-- first try to update the key...
Insert into a MySQL table or update if exists
...m what I've found, this method is less problematic for auto-increment keys and other unique key collisions than REPLACE INTO, and it is more efficient.
– Andrew Ensley
May 11 '12 at 21:27
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