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PostgreSQL return result set as JSON array?
... up
The json_agg function produces this result out of the box. It automatically figures out how to convert its input into JSON and aggregates it into an array.
SELECT json_agg(t) FROM t
There is no jsonb (introduced in 9.4) version of json_agg. You can either aggregate the rows into an array and...
How is set() implemented?
...ly to allow this? What sort of data structure does it use? What other implications does that implementation have?
5 Answers...
Detect Chrome extension first run / update
How can an extension find out that it is being run for the first time or has just been updated, so that the extension can perform some specific actions? (e.g. open a help page or update settings)
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Streaming a video file to an html5 video player with Node.js so that the video controls continue to
...00, { "Content-Type": "text/html" });
res.end('<video src="http://localhost:8888/movie.mp4" controls></video>');
} else {
var file = path.resolve(__dirname,"movie.mp4");
fs.stat(file, function(err, stats) {
if (err) {
if (err.code === 'ENOENT') {
// ...
What is the difference between Class Path and Build Path
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The build path is used for building your application. It contains all of your source files and all Java libraries that are required to compile the application.
The classpath is used for executing the application. This includes all java classes and libraries that are nee...
Convert.ChangeType() fails on Nullable Types
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@threadster You can't use default operator ona variable of type 'Type'. See stackoverflow.com/questions/325426/…
– andy250
Dec 3 '19 at 16:53
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client secret in OAuth 2.0
To use google drive api, I have to play with the authentication using OAuth2.0. And I got a few question about this.
3 Answ...
arrayfun can be significantly slower than an explicit loop in matlab. Why?
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You can get the idea by running other versions of your code. Consider explicitly writing out the computations, instead of using a function in your loop
tic
Soln3 = ones(T, N);
for t = 1:T
for n = 1:N
Soln3(t, n) = 3*...
What is the difference between named and positional parameters in Dart?
...uss the similarities.
Dart's optional parameters are optional in that the caller isn't required to specify a value for the parameter when calling the function.
Optional parameters can only be declared after any required parameters.
Optional parameters can have a default value, which is used when ...
Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
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