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How to do joins in LINQ on multiple fields in single join
...r a second from clause) IMO. You could do some particularly funky magic by ordering one side or the other to find matches more efficiently, but that would be a lot of work - I'd only do that kind of thing after checking whether performance is an issue.
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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),...
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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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...
Is it possible to focus on a using JavaScript focus() function?
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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...
Get an array of list element contents in jQuery
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Does jQuery guarantee an order to the elements returned by the query? I would assume that the order returned is the same as the ordering in the DOM (ie text1, text2, text3), but I don't know what to look for in the documentation to see if this is tru...
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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Transferring an app to another Firebase account
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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
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Callback after all asynchronous forEach callbacks are completed
...ue of the index parameter does not provide the same guarantee, because the order of return of the asynchronous operations is not guaranteed.
Using ES6 Promises
(a promise library can be used for older browsers):
Process all requests guaranteeing synchronous execution (e.g. 1 then 2 then 3)
func...
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
\ | / \
\ | / |
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B C
\ /
\ /
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