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Delete all but the most recent X files in bash
... but the 5 last lines (ie the 5 newest files).
xargs rm calls rm for each selected file.
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How to select a single field for all documents in a MongoDB collection?
...nt such as:
db.student.find({}, {roll:1, _id:0})
The above statement will select all documents in the students collection, and the returned document will return only the roll field (and exclude the _id).
If we don't mention _id:0 the fields returned will be roll and _id. The '_id' field is always d...
Set select option 'selected', by value
I have a select field with some options in it. Now I need to select one of those options with jQuery. But how can I do that when I only know the value of the option that must be selected?
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SQL join: selecting the last records in a one-to-many relationship
... want to get a list of all customers along with their last purchase in one SELECT statement. What is the best practice? Any advice on building indexes?
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ruby on rails f.select options with custom attributes
I have a form select statement, like this:
5 Answers
5
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string.split - by multiple character delimiter
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This presupposes, that there are both characters right? What if I want to split by either "[" or "]"? From my tests so far I guess thats a different story, right?
– C4d
Mar 7 '16 at 15:28
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How to securely save username/password (local)?
... textBox2.Text = readable;
}
groupBox1.Select();
}
static byte[] entropy = Encoding.Unicode.GetBytes("SaLtY bOy 6970 ePiC");
public static string EncryptString(SecureString input)
{
byte[] encryptedData = ProtectedDat...
Retrieving the last record in each group - MySQL
...x, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m
)
SELECT * FROM ranked_messages WHERE rn = 1;
Below is the original answer I wrote for this question in 2009:
I write the solu...
jQuery - getting custom attribute from selected option
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You're adding the event handler to the <select> element.
Therefore, $(this) will be the dropdown itself, not the selected <option>.
You need to find the selected <option>, like this:
var option = $('option:selected', this).attr('mytag');
...
When should I use nil and NULL in Objective-C?
...ke a C pointer) in Objective-C. Like nil , NULL got no value nor address.
char *myChar = NULL;
struct MyStruct *dStruct = NULL;
So if there is a situation, when I need to check my struct (structure type variable) is empty or not then, I will use:
if (dStruct == NULL)
NSLog("The struct is emp...