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mongodb: insert if not exists
... This is almost what I want ! How can I not touch the insertion_date field if the object is already present ?
– LeMiz
May 27 '10 at 21:24
28
...
Max or Default?
...t I think it'd go something like this:
Dim x = (From y In context.MyTable _
Where y.MyField = value _
Select CType(y.MyCounter, Integer?)).Max
Or in C#:
var x = (from y in context.MyTable
where y.MyField == value
select (int?)y.MyCounter).Max();
...
Is there a Python function to determine which quarter of the year a date is in?
...calDate.today()
>>> a
FiscalDate(2017, 5, 6)
>>> a.fiscal_year
2017
>>> a.quarter
3
>>> b = FiscalYear(2017)
>>> b.start
FiscalDateTime(2016, 10, 1, 0, 0)
>>> b.end
FiscalDateTime(2017, 9, 30, 23, 59, 59)
>>> b.q3
FiscalQuarter(2017, 3)
...
What are valid values for the id attribute in HTML?
...wed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").
HTML 5 is even more permissive, saying only that an id must contain at least one character and may not contain any space characters.
The id attribute is case sensitive in XHTML.
As a ...
how do you filter pandas dataframes by multiple columns
...er and that depend on more than one column, you can use:
df = df[df[['col_1','col_2']].apply(lambda x: f(*x), axis=1)]
where f is a function that is applied to every pair of elements (x1, x2) from col_1 and col_2 and returns True or False depending on any condition you want on (x1, x2).
...
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...
Restrictions
You can ask the system catalog pg_database - accessible from any database in the same database cluster. The tricky part is that CREATE DATABASE can only be executed as a single statement. The manual:
CREATE DATABASE cannot be executed inside a transaction b...
Declaring an enum within a class
...uct Color
{
enum Type
{
Red, Green, Black
};
Type t_;
Color(Type t) : t_(t) {}
operator Type () const {return t_;}
private:
//prevent automatic conversion for any other built-in types such as bool, int, etc
template<typename T>
operator T () const;
};
...
Passing parameters to addTarget:action:forControlEvents
... creating several buttons within a for loop:
for (NSInteger i = 0; i < _phoneNumbers.count; i++) {
UIButton *phoneButton = [[UIButton alloc] initWithFrame:someFrame];
[phoneButton setTitle:_phoneNumbers[i] forState:UIControlStateNormal];
[phoneButton setTag:i];
[phoneButton ad...
Java ByteBuffer to String
...sibling getBytes() method:
byte[] bytes = k.getBytes( StandardCharsets.UTF_8 );
To put bytes with a particular encoding into a String, you can use a different String constructor:
String v = new String( bytes, StandardCharsets.UTF_8 );
Note that ByteBuffer.array() is an optional operation. If y...
PHP script to loop through all of the files in a directory?
...r. Example from php Manual:
<?php
$dir = new DirectoryIterator(dirname(__FILE__));
foreach ($dir as $fileinfo) {
if (!$fileinfo->isDot()) {
var_dump($fileinfo->getFilename());
}
}
?>
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