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Drawing an SVG file on a HTML5 canvas
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Mozilla has a simple way for drawing SVG on canvas called "Drawing DOM objects into a canvas"
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When to use inline function and when not to use it?
...hat inline is a hint or request to compiler and its used to avoid function call overheads.
14 Answers
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Oracle Differences between NVL and Coalesce
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SELECT SUM(val)
FROM (
SELECT NVL(1, LENGTH(RAWTOHEX(SYS_GUID()))) AS val
FROM dual
CONNECT BY
level <= 10000
)
This runs for almost 0.5 seconds, since it generates SYS_GUID()'s, despite 1 being not a NULL.
SELECT SUM(val)
FROM (
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LinkedBlockingQueue vs ConcurrentLinkedQueue
... the fundamental interface for producer/consumer queues IMO. You'd have to call poll(), wait a bit if you hadn't found anything, and then poll again etc... leading to delays when a new item comes in, and inefficiencies when it's empty (due to waking up unnecessarily from sleeps).
From the docs for ...
What is an application binary interface (ABI)?
... but the API does not, then the old and new library versions are sometimes called "source compatible". This implies that while a program compiled for one library version will not work with the other, source code written for one will work for the other if re-compiled.
For this reason, developers te...
set the width of select2 input (through Angular-ui directive)
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You need to specify the attribute width to resolve in order to preserve element width
$(document).ready(function() {
$("#myselect").select2({ width: 'resolve' });
});
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Why use the params keyword?
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With params you can call your method like this:
addTwoEach(1, 2, 3, 4, 5);
Without params, you can’t.
Additionally, you can call the method with an array as a parameter in both cases:
addTwoEach(new int[] { 1, 2, 3, 4, 5 });
That is, pa...
How to permanently add a private key with ssh-add on Ubuntu? [closed]
... files to be kept permanently, by adding them in your ~/.ssh/config file:
IdentityFile ~/.ssh/gitHubKey
IdentityFile ~/.ssh/id_rsa_buhlServer
If you do not have a 'config' file in the ~/.ssh directory, then you should create one. It does not need root rights, so simply:
nano ~/.ssh/config
...a...
When is a C++ destructor called?
Basic Question: when does a program call a class' destructor method in C++? I have been told that it is called whenever an object goes out of scope or is subjected to a delete
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How to update column with null value
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No special syntax:
CREATE TABLE your_table (some_id int, your_column varchar(100));
INSERT INTO your_table VALUES (1, 'Hello');
UPDATE your_table
SET your_column = NULL
WHERE some_id = 1;
SELECT * FROM your_table WHERE your_column IS NULL;
+---------+-------------+
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