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Difference between Django's annotate and aggregate methods?
...gt; q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been annotated with the number of authors.
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Positions fixed doesn't work when using -webkit-transform
...g it as the background.
@media screen and (-webkit-min-device-pixel-ratio:0) {
/* Webkit-specific CSS here (Chrome and Safari) */
#transformed_div {
/* styles here, background image etc */
}
}
So for now you'll have to do it the old fashioned way, until Webkit browsers catch up to FF.
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Splitting a string into chunks of a certain size
...;string> Split(string str, int chunkSize)
{
return Enumerable.Range(0, str.Length / chunkSize)
.Select(i => str.Substring(i * chunkSize, chunkSize));
}
Please note that additional code might be required to gracefully handle edge cases (null or empty input string, chunkSize == 0, ...
How should I escape commas and speech marks in CSV files so they work in Excel?
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answered Sep 18 '12 at 8:50
centralscrucentralscru
6,03633 gold badges2828 silver badges3636 bronze badges
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Drawing a line/path on Google Maps
... mPaint.setStrokeWidth(2);
GeoPoint gP1 = new GeoPoint(19240000,-99120000);
GeoPoint gP2 = new GeoPoint(37423157, -122085008);
Point p1 = new Point();
Point p2 = new Point();
Path path = new Path();
Projection projection=mapv.getProjection();...
is of a type that is invalid for use as a key column in an index
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A unique constraint can't be over 8000 bytes per row and will only use the first 900 bytes even then so the safest maximum size for your keys would be:
create table [misc_info]
(
[id] INTEGER PRIMARY KEY IDENTITY NOT NULL,
[key] nvarchar(450) UNIQUE...
Razor View Engine : An expression tree may not contain a dynamic operation
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301
It seems to me that you have an untyped view. By default, Razor views in MVC3 RC are typed as d...
What are commit-ish and tree-ish in Git?
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160
The Short Answer (TL;DR)
Here's a complete list of commit-ish and tree-ish identifiers (from th...
How to add text to a WPF Label in code?
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answered Feb 4 '11 at 20:14
Daniel A. WhiteDaniel A. White
170k4242 gold badges334334 silver badges403403 bronze badges
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How to write DataFrame to postgres table?
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Starting from pandas 0.14 (released end of May 2014), postgresql is supported. The sql module now uses sqlalchemy to support different database flavors. You can pass a sqlalchemy engine for a postgresql database (see docs). E.g.:
from sqlalchemy...