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sql primary key and index
...ional index does no good, but the only harm (very small) is the additional file size and row-creation overhead.
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Is a LINQ statement faster than a 'foreach' loop?
...cts generally is going to add some marginal overheads (multiple iterators, etc). It still has to do the loops, and has delegate invokes, and will generally have to do some extra dereferencing to get at captured variables etc. In most code this will be virtually undetectable, and more than afforded b...
jQuery or javascript to find memory usage of page
...t.
Fixed content is not dependant on user actions (memory used by script files, plugins, etc.)
Everything else is considered dynamic and should be your main focus when determining your limit.
But there is no easy way to summarize them. You could implement a tracking system that gathers all these ...
What is the difference between a stored procedure and a view?
...g block in a larger query
Can contain several statements, loops, IF ELSE, etc.
Can perform modifications to one or several tables
Can NOT be used as the target of an INSERT, UPDATE or DELETE
statement.
A View:
Does NOT accept parameters
Can be used as building block in a larger query
Can...
How can I capture the result of var_dump to a string?
... => array(),
"object" => new stdClass(),
"resource" => tmpfile(),
"null" => null,
);
// var_export -- nice, one-liner
$debug_export = var_export($demo, true);
// var_dump
ob_start();
var_dump($demo);
$debug_dump = ob_get_clean();
// print_r -- included for completeness, th...
Why can outer Java classes access inner class private members?
...her XYZ should really be an inner class and that maybe it deserves its own file. Sometimes it makes sense to create a static inner class (for example, if you need a small class that implements an interface your outer class is using, and that won't be helpful anywhere else). But at about half of the ...
Different bash prompt for different vi editing mode?
...f you are running bash 4.3 or higher, add the following to your ~/.inputrc file set show-mode-in-prompt This adds a + to the very left of your prompt if you are in edit mode, and a : if you are in command mode.
– stooj
Mar 29 '14 at 4:25
...
Cron job every three days
... you want it to run on specific days of the month, like the 1st, 4th, 7th, etc... then you can just have a conditional in your script that checks for the current day of the month.
if (((date('j') - 1) % 3))
exit();
or, as @mario points out, you can use date('k') to get the day of the year inst...
How to debug Ruby scripts [closed]
...
with -rdebug :no need to change source file in order to debug
– germanlinux
Sep 23 '14 at 21:18
2
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How to check for a valid Base64 encoded string
..., especially if the string is large (which happens when transferring large files). The following approach tries the fastest ways of detection first.
public static class HelperExtensions {
// Characters that are used in base64 strings.
private static Char[] Base64Chars = new[] { 'A', 'B', 'C...