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Difference between clustered and nonclustered index [duplicate]
...a completely different object within the table that contains the column(s) selected for indexing and a pointer back to the table’s rows containing the data. It is like an index in the last pages of a book, where keywords are sorted and contain the page number to the material of the book for faster...
MySQL: how to get the difference between two timestamps in seconds
...
You could use the TIMEDIFF() and the TIME_TO_SEC() functions as follows:
SELECT TIME_TO_SEC(TIMEDIFF('2010-08-20 12:01:00', '2010-08-20 12:00:00')) diff;
+------+
| diff |
+------+
| 60 |
+------+
1 row in set (0.00 sec)
You could also use the UNIX_TIMESTAMP() function as @Amber suggested in a...
Apache Prefork vs Worker MPM
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See also "How do I select which Apache MPM to use?" serverfault.com/a/383634
– Nazariy
Dec 18 '13 at 12:17
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android get real path by Uri.getPath()
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This is what I do:
Uri selectedImageURI = data.getData();
imageFile = new File(getRealPathFromURI(selectedImageURI));
and:
private String getRealPathFromURI(Uri contentURI) {
String result;
Cursor cursor = getContentResolver().query(cont...
How to write “Html.BeginForm” in Razor
...data" }))
{
@Html.ValidationSummary(true)
<fieldset>
Select a file <input type="file" name="file" />
<input type="submit" value="Upload" />
</fieldset>
}
and generates as expected:
<form action="/Upload/Upload" enctype="multipart/form-data" m...
Create new user in MySQL and give it full access to one database
...';
Where ALL (priv_type) can be replaced with specific privilege such as SELECT, INSERT, UPDATE, ALTER, etc.
Then to reload newly assigned permissions run:
FLUSH PRIVILEGES;
Executing
To run above commands, you need to run mysql command and type them into prompt, then logout by quit command...
Create boolean column in MySQL with false as default value?
... into mytable () values ();
Query OK, 1 row affected (0.00 sec)
mysql> select * from mytable;
+--------+
| mybool |
+--------+
| 0 |
+--------+
1 row in set (0.00 sec)
FYI: My test was done on the following version of MySQL:
mysql> select version();
+----------------+
| version() ...
Hidden features of Perl?
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One of my favourite features in Perl is using the boolean || operator to select between a set of choices.
$x = $a || $b;
# $x = $a, if $a is true.
# $x = $b, otherwise
This means one can write:
$x = $a || $b || $c || 0;
to take the first true value from $a, $b, and $c, or a default of 0...
Randomize a List
...uffle();
The code above uses the much criticised System.Random method to select swap candidates. It's fast but not as random as it should be. If you need a better quality of randomness in your shuffles use the random number generator in System.Security.Cryptography like so:
using System.Security....
Breakpoints are crossed out, how can I make them valid?
...akpoints' in eclipse.
When you click on 'skip all breakpoints'(which is selected), everything will become normal
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