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SQL JOIN vs IN performance?
...
That's rather hard to say - in order to really find out which one works better, you'd need to actually profile the execution times.
As a general rule of thumb, I think if you have indices on your foreign key columns, and if you're using only (or mostly) INNER JOIN conditions, then the ...
Is there a way to check if a file is in use?
...g(FileStream stream = file.Open(FileMode.Open, FileAccess.Read, FileShare.None))
{
stream.Close();
}
}
catch (IOException)
{
//the file is unavailable because it is:
//still being written to
//or being processed by another thread
...
Tags for Emacs: Relationship between etags, ebrowse, cscope, GNU Global and exuberant ctags
...ng invoked, etc (you can find definitions as well).
To sum it up:
ctags one allows you to navigate to symbol declaration/definitions (what some would call a one-way lookup). ctags is a general purpose tool useful for many languages.
On the other hand (as mentioned on the project's page) cscope a...
Round a double to 2 decimal places [duplicate]
...o, use this instead
(Adapted from this answer by Louis Wasserman and this one by Sean Owen.)
public static double round(double value, int places) {
if (places < 0) throw new IllegalArgumentException();
BigDecimal bd = BigDecimal.valueOf(value);
bd = bd.setScale(places, RoundingMode...
Remove all multiple spaces in Javascript and replace with single space [duplicate]
... lot of options for regular expressions you could use to accomplish this. One example that will perform well is:
str.replace( /\s\s+/g, ' ' )
See this question for a full discussion on this exact problem: Regex to replace multiple spaces with a single space
...
How can I get this ASP.NET MVC SelectList to work?
...pDown", ViewBag.PageOptions as IEnumerable<SelectListItem>, "(Select one)")
It will result in the desired output--of course, you can leave out the "(Select one)" optionLabel above if you don't want the first empty item:
<select id="PageOptionsDropDown" name="PageOptionsDropDown">
<...
Access restriction: The type 'Application' is not API (restriction on required library rt.jar)
...n and the comment from Jonathan. In the tab Libraries you have to open the one among the listed "JARs and class folders" to see the "Access rules" belongs to it.
– Laszlo Hirdi
Jan 13 '16 at 16:28
...
Transferring ownership of an iPhone app on the app store
...at we'll be selling the app to another company in the near future. Does anyone have any experience with moving an app's ownership to another account?
...
Convert absolute path into relative path given a current directory using Bash
... # no match, means that candidate common part is not correct
# go up one level (reduce common part)
common_part="$(dirname $common_part)"
# and record that we went back, with correct / handling
if [[ -z $result ]]; then
result=".."
else
result="../$result"
f...
“Eliminate render-blocking CSS in above-the-fold content”
...ntent!
Additionally why do you use different CSS files, rather than just one?
The additional request is worse than the small amount of data volume. And after the first request the CSS file is cached anyway.
The things one should always take care of are:
reduce the number of requests as much a...