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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...
How to split strings across multiple lines in CMake?
...ERSION_LIST})
-- Version: 1.0.0-rc1
If you really need a string, you can convert the list to a string first:
string(REPLACE ";" "" MYPROJ_VERSION "${MYPROJ_VERSION_LIST}")
message(STATUS "Version: ${MYPROJ_VERSION}")
-- Version: 1.0.0-rc1
Any semicolons in your original strings will be seen as ...
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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Difference between string and char[] types in C++
... and certain functions may only accept a string as input, requiring you to convert the array to a string. It's better to use strings, they were made so that you don't have to use arrays. If arrays were objectively better we wouldn't have strings.
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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...
Can I incorporate both SignalR and a RESTful API?
I have a single page web app developed using ASP.NET. I recently converted many of the web methods to be push based, using the SignalR library. This really sped up the page considerably and reduced a lot of the server calls from the page.
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Docker - a way to give access to a host USB or serial device?
...ber. Some common device major numbers:
81: usb webcams
188: usb to serial converters
Step 2
Add rules when you start the docker container:
Add a --device-cgroup-rule='c major_number:* rmw' rule for every type of device you want access to
Add access to udev information so docker containers can get...
Init method in Spring Controller (annotation version)
I'm converting a controller to the newer annotation version. In the old version I used to specify the init method in springmvc-servlet.xml using:
...