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In .NET, which loop runs faster, 'for' or 'foreach'?
...tably faster, why shouldn't you start using it in general? It doesn't take extra time.
– DevinB
Sep 3 '09 at 13:06
50
...
PHP: Storing 'objects' inside the $_SESSION
...on objects based on the ID the client submitted with the request. All this extra work is a double whammy on scalability (a big reason HTTP is stateless).
Whammy One: It reduces the work a single server can do.
Whammy Two: It makes it harder to scale out because now you can't just route a request t...
Why Collections.sort uses merge sort instead of quicksort?
...ast stable sort that guarantees O(n log n)
performance and requires O(n) extra space. In its day (it was written
in 1997 by Joshua Bloch), it was a fine choice, but today but we can
do much better.
Since 2003, Python's list sort has used an algorithm known as timsort
(after Tim Peters,...
Can I run multiple versions of Google Chrome on the same machine? (Mac or Windows)
...fo.plist and change the value of <key>KSUpdateURL</key> to <string>https://tools.google.com/abcdefg</string>. No other method worked for me (including setting defaults write com.google.Keystone.Agent checkInterval 0).
– Abhishek Divekar
...
Declaring a custom android UI element using XML
...xtColor"/>
<attr name="extraInformation" format="string" />
</declare-styleable>
</resources>
Notice the use of an unqualified name in the declare-styleable tag. Non-standard android attributes like extraInformation need to have their type declared. Ta...
Securely storing environment variables in GAE with app.yaml
...m google.appengine.ext import ndb
class Settings(ndb.Model):
name = ndb.StringProperty()
value = ndb.StringProperty()
@staticmethod
def get(name):
NOT_SET_VALUE = "NOT SET"
retval = Settings.query(Settings.name == name).get()
if not retval:
retval = Settings()
retva...
SQL Server equivalent to MySQL enum data type?
... then you'll end-up adding lots of tables to your database. Not to mention extra IO reads due to FK constraint-checking when inserting/deleting data, whereas a CHECK CONSTRAINT is much faster and doesn't cause database object spam.
– Dai
Sep 18 at 7:23
...
How do I pass variables and data from PHP to JavaScript?
...beyond, limbo, the city of shimmers, and Canada.
*
* AJAX generally uses strings, but you can output JSON, HTML and XML as well.
* It all depends on the Content-type header that you send with your AJAX
* request. */
echo json_encode(42); // In the end, you need to echo the result.
...
How to ignore xargs commands if stdin input is empty?
... may take advantage of -L <#lines>, -n <#args>, -i, and -I <string>:
ls /empty_dir/ | xargs -n10 chown root # chown executed every 10 args or fewer
ls /empty_dir/ | xargs -L10 chown root # chown executed every 10 lines or fewer
ls /empty_dir/ | xargs -i cp {} {}.bak # every {} is ...
Determine Whether Two Date Ranges Overlap
...a syntactical shortcut for what is a longer implementation, which includes extra checks to verify that the start dates are on or before the endDates. Deriving this from above:
If start and end dates can be out of order, i.e., if it is possible that startA > endA or startB > endB, then you a...