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postgresql return 0 if returned value is null
...he second is if there are NULL values in the query.
For all versions I've tested, postgres and mysql will ignore all NULL values when averaging, and it will return NULL if there is nothing to average over. This generally makes sense, as NULL is to be considered "unknown". If you want to override t...
Using multiple let-as within a if-statement in Swift
...two values from a dictionary and before using them I have to cast them and test for the right type. This is what I came up with:
...
Difference between Destroy and Delete
...ased on the :dependent option passed into the association. However, during testing, I found the following side effect where callbacks were only ran for delete and not delete_all
dependent: :destroy Example:
class Parent < ApplicationRecord
has_many :children,
before_remove: -> (_) {...
“From View Controller” disappears using UIViewControllerContextTransitioning
...
wow. That did it! I tested without modalPresentationStyle in iOS7 & 8 and it works find in both. Thanks!!
– Ah Ryun Moon
Sep 9 '14 at 23:26
...
How do I find the most recent git commit that modified a file?
... relative path names with wildcards, for ex:
git rev-list origin/user/bob/testbranch -1 src/bfiles/*.txt
...Which would tell you what the most recent change was to the wildcard match in that branch's history. The options for rev-list are extreme, it is one of the most important plumbing commands,...
PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
...for pdo_mysql module. Maybe there are much more bugs, I don't know. Also I tested on fresh 64bit debian jessie, all listed bugs occur when I apt-get install php5-mysql, and disappear when I apt-get install php5-mysqlnd.
When PDO::ATTR_EMULATE_PREPARES is set to true (as default) - these bugs don't ...
What does the restrict keyword mean in C++?
...oth are the same.
With -O3:
with restrict:
3f0: 48 85 d2 test %rdx,%rdx
3f3: 74 33 je 428 <fr+0x38>
3f5: 55 push %rbp
3f6: 53 push %rbx
3f7: 48 89 f5 mov %rsi,%rbp
3fa: be 04 00 ...
How can I push a local Git branch to a remote with a different name easily?
... branch name I've checked out. I might just want to git push buildserver .:test_this where the . shall be the local branch name which I don't necessarily know. I could look it up, sure, but if there was a short hand, like the dot, for that, it'd be cool.
– Frederick Nord
...
Compression/Decompression string with C#
...ould it ever change
using (var compressorStream = new DeflateStream(compressedStream, CompressionLevel.Fastest, true))
{
uncompressedStream.CopyTo(compressorStream);
}
// call compressedStream.ToArray() after the en...
Submitting HTML form using Jquery AJAX
... $.post documentation.
Example: Send form data using ajax requests
$.post("test.php", $("#testform").serialize());
Example: Post a form using ajax and put results in a div
<!DOCTYPE html>
<html>
<head>
<script src="http://code.jquery.com/jquery-1.9.1.js"></scr...