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Can I have multiple primary keys in a single table?
...hese practices, but there is nothing in the relational model that requires selecting a primary key among the candidate keys.
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How do I force Postgres to use a particular index?
...d, client_id, date, and description. You want to run the following query:
SELECT client_id, SUM(amount)
FROM transactions
WHERE date >= 'yesterday'::timestamp AND date < 'today'::timestamp AND
description = 'Refund'
GROUP BY client_id
PostgreSQL may choose to use the index transaction...
Difference between GeoJSON and TopoJSON
...aScript, for example, you’d typically use the TopoJSON client library to convert TopoJSON to GeoJSON for use with standard tools such as d3.geoPath. (In Python, you can use topojson.py.) Also, TopoJSON’s integer format requires quantizing coordinates, which means that it can introduce rounding e...
Visual Studio: Relative Assembly References Paths
...n Visual Studio GUI by right-clicking the project in Solution Explorer and selecting Add Reference...
Find the *.csproj where this reference exist and open it in a text editor
Edit the < HintPath > to be equal to
<HintPath>..\..\myReferences\myDLL.dll</HintPath>
This now refer...
Using CSS how to change only the 2nd column of a table
...
@Deeksy - That's not accurate, it doesn't care what the selector is. nth-child is applied after finding the element, and it's nth compared to whatever parent it has, no matter if it was in the selector or not. You can see this working here: jsfiddle.net/JQQPz
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Getting exact error type in from DbValidationException
... string errorMessages = string.Join("; ", ex.EntityValidationErrors.SelectMany(x => x.ValidationErrors).Select(x => x.PropertyName + ": " + x.ErrorMessage));
throw new DbEntityValidationException(errorMessages);
}
}
This will overwrite your context's SaveChanges() method a...
Min/Max-value validators in asp.net mvc
... }
public override bool IsValid(object value)
{
return Convert.ToDouble(value) >= _minValue;
}
public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
{
var rule = new ModelClientValid...
Has anyone used Coffeescript for a production application? [closed]
...concern. It's entirely likely, from the text I've given, that we've simply converted already working javascript into coffeescript, hence no serious debugging is yet required
– PandaWood
Jan 30 '12 at 0:58
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Update git commit author date when amending
... in the source code of git(1) in date.c 'now' is a special value which is converted using date_now() function. Same for 'noon', 'yesterday', 'midnight', 'tea' and others listed in the structure array special[].
– sbz
Jul 29 '16 at 0:18
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How to set DialogFragment's width and height?
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If you convert directly from resources values:
int width = getResources().getDimensionPixelSize(R.dimen.popup_width);
int height = getResources().getDimensionPixelSize(R.dimen.popup_height);
getDialog().getWindow().setLayou...