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Difference between natural join and inner join
...aspect of a natural join. The things you need to know are (A) it automatically joins on fields of the same name and (B) it will f*** up your s*** when you least expect it. In my world, using a natural join is grounds for dismissal.
– user565869
Jan 6 '14 at 1...
Detect Chrome extension first run / update
...versions of Chrome (since Chrome 22), you can use the chrome.runtime.onInstalled event, which is much cleaner.
Example:
// Check whether new version is installed
chrome.runtime.onInstalled.addListener(function(details){
if(details.reason == "install"){
console.log("This is a first inst...
Select DISTINCT individual columns in django?
...g note in the docs about using distinct(). The above example will work but all combinations of distinct() and values() may not.
PS: it is a good idea to use lower case names for fields in a model. In your case this would mean rewriting your model as shown below:
class ProductOrder(models.Model):
...
What is the difference between the hidden attribute (HTML5) and the display:none rule (CSS)?
...abbed interface is merely a kind of overflow presentation — one could equally well just show all the form controls in one big page with a scrollbar. It is similarly incorrect to use this attribute to hide content just from one presentation — if something is marked hidden, it is hidden from all p...
Turning multi-line string into single comma-separated
... awk: invalid -v option :(
– Marsellus Wallace
Jun 15 '15 at 17:38
6
Add a space bet...
What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
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What is ECMAScript?
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JavaScript is a subset of ECMAScript. JavaScript is basically ECMAScript at its core but builds upon it. Languages such as ActionScript, JavaScript, JScript all use ECMAScript as its core. As a comparison, AS/JS/JScript are 3 different cars, but they all use the same engine... each...
Node.js EACCES error when listening on most ports
...'m testing out an app (hopefully to run on heroku, but am having issues locally as well). It's giving me an EACCES error when it runs http.Server.listen() - but it only occurs on some ports.
...
Sort Dictionary by keys
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this actually returns an array of [(String, [Int])] not a Dictionary
– scord
Feb 12 '16 at 16:27
4
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Multiple working directories with Git?
...ktree section adds:
A git repository can support multiple working trees, allowing you to check out more than one branch at a time.
With git worktree add, a new working tree is associated with the repository.
This new working tree is called a "linked working tree" as opposed to the "main working ...