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Give all the permissions to a user on a DB
...user needs access to the database, obviously:
GRANT CONNECT ON DATABASE my_db TO my_user;
And (at least) the USAGE privilege on the schema:
GRANT USAGE ON SCHEMA public TO my_user;
Or grant USAGE on all custom schemas:
DO
$$
BEGIN
-- RAISE NOTICE '%', ( -- use instead of EXECUTE to see ge...
What's the difference between Perl's backticks, system, and exec?
...t, and don't want to wait for it to return. system is really just
sub my_system {
die "could not fork\n" unless defined(my $pid = fork);
return waitpid $pid, 0 if $pid; #parent waits for child
exec @_; #replace child with new process
}
You may also want to read the waitpid and perli...
What are the differences between Deferred, Promise and Future in JavaScript?
...es from [Functional Reactive Programming|haskell.org/haskellwiki/Functional_Reactive_Programming], which is a technique for flattening callbacks."
– fncomp
Feb 11 '13 at 5:32
2
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Integrate ZXing in Android Studio
...tIntegrator(this);
integrator.setDesiredBarcodeFormats(IntentIntegrator.ONE_D_CODE_TYPES);
integrator.setPrompt("Scan a barcode");
integrator.setCameraId(0); // Use a specific camera of the device
integrator.setBeepEnabled(false);
integrator.setBarcodeImageEnabled(true);
integrator.initiateScan();
...
Difference between Destroy and Delete
...ary key, and no callbacks are executed.
To enforce the object's before_destroy and after_destroy callbacks or any :dependent association options, use #destroy.
ActiveRecord::Persistence.destroy
Deletes the record in the database and freezes this instance to reflect that no changes should b...
ActiveRecord: size vs count
...e a new record without going through the relation, i.e. Comment.create(post_id: post.id), your post.comments.size will not be up to date, while post.comments.count will. So just be careful.
– mrbrdo
Mar 31 '13 at 19:52
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What is a semaphore?
...interestingly it has already been used: albahari.com/threading/part2.aspx#_Semaphore
– Igor Brejc
Mar 27 '15 at 8:50
...
TCP vs UDP on video stream
...occer-fans and the internet itself is against me so I figure it's my loss ^_^
– Alxandr
May 31 '11 at 12:46
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show 2 more comments
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Percentage Height HTML 5/CSS
... edited Feb 18 '17 at 5:54
Web_Designer
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answered Oct 25 '09 at 21:15
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When do you use map vs flatMap in RxJava?
...ten" this observable of observables (you might start to see where the name _flat_Map comes from). RxJava provides a few ways to flatten observables and for sake of simplicity lets assume merge is what we want. Merge basically takes a bunch of observables and emits whenever any of them emits. (Lots o...