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How do I do a not equal in Django queryset filtering?
... @danigosa That doesn't seem right. I just tried this myself, and the order of exclude and filter calls didn't make any meaningful difference. The order of the conditions in the WHERE clause changes, but how does that matter?
– coredumperror
Apr 7 '16 at 1...
Why is volatile not considered useful in multithreaded C or C++ programming?
...egister instead and defer updating main memory until much later)
that no reordering takes place. Assume that we use a volatile variable as a flag to indicate whether or not some data is ready to be read. In our code, we simply set the flag after preparing the data, so all looks fine. But what if the...
What columns generally make good indexes?
...nto your tables:
Only index those columns that are required in WHERE and ORDER BY clauses. Indexing columns in abundance will result in some disadvantages.
Try to take benefit of "index prefix" or "multi-columns index" feature of MySQL. If you create an index such as INDEX(first_name, last_name),...
Is it possible to focus on a using JavaScript focus() function?
...
Yes - this is possible. In order to do it, you need to assign a tabindex...
<div tabindex="0">Hello World</div>
A tabindex of 0 will put the tag "in the natural tab order of the page". A higher number will give it a specific order of pri...
Gulp command not found after install
...ed the npm root -g was pointing to /usr/local/lib/node_modules/npm, but in order to install gulp in /usr/local/lib/node_modules, I had to use sudo:
sudo npm install gulp -g
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How can I position my div at the bottom of its container?
...ement seeks it's closest parent that is absolute or relatively position in order to determine it's position. If all fails it resorts to body (window). So hence the need for the parent to be relative.
– user17753
Jun 13 '12 at 18:46
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How can I read a large text file line by line using Java?
...les.lines(Paths.get(filename), Charset.defaultCharset())) {
lines.forEachOrdered(line -> process(line));
}
Printing all the lines in the file:
try (Stream<String> lines = Files.lines(file, Charset.defaultCharset())) {
lines.forEachOrdered(System.out::println);
}
...
What's the difference between HEAD^ and HEAD~ in Git?
...Both commit nodes B and C are parents of commit node A. Parent commits are ordered left-to-right. (N.B. The git log --graph command displays history in the opposite order.)
G H I J
\ / \ /
D E F
\ | / \
\ | / |
\|/ |
B C
\ /
\ /
...
Transferring an app to another Firebase account
...
worked like a charm :) I wanted to add a new owner in order to switch google play account linked with Firebase project.
– Wahib Ul Haq
Jul 23 '17 at 18:34
7
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Why is SELECT * considered harmful?
...code saves more time and effort in the long run.
If code depends on column order, SELECT * will hide an error waiting to happen if a table had its column order changed.
Even if you need every column at the time the query is written, that might not be the case in the future
the usage complicates pro...