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LINQ - Left Join, Group By, and Count
...into j1
from j2 in j1.DefaultIfEmpty()
group j2 by p.ParentId into grouped
select new { ParentId = grouped.Key, Count = grouped.Count(t=>t.ChildId != null) }
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Modifying a subset of rows in a pandas dataframe
...The df.A==0 expression creates a boolean series that indexes the rows, 'B' selects the column. You can also use this to transform a subset of a column, e.g.:
df.loc[df.A==0, 'B'] = df.loc[df.A==0, 'B'] / 2
I don't know enough about pandas internals to know exactly why that works, but the basic is...
What is the use of GO in SQL Server Management Studio & Transact SQL?
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gbn make it SELECT and look at what happens :-)
– SQLMenace
Feb 19 '10 at 21:09
14
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MySQL indexes - what are the best practices?
...t them. Generally I put an index on any fields that I will be searching or selecting using a WHERE clause but sometimes it doesn't seem so black and white.
...
Xcode is not currently available from the Software Update server
...e Xcode command line tools is pointed correctly using this command
xcode-select -p
Which might show some path like
/Applications/Xcode.app/Contents/Developer
Change the path to correct path using the switch command
xcode-select --switch /Library/Developer/CommandLineTools/
this should...
How to select different app.config for several build configurations
...ctory. So if you had PatternPA.Test.Integration project and a Debug config selected, in the output folder after the build you will find a PatternPA.Test.Integration.dll.config file which was copied from Config\App.Debug.config and renamed afterwards.
These are some notes you can leave in the config...
How do I clear all options in a dropdown box?
...
You can use the following to clear all the elements.
var select = document.getElementById("DropList");
var length = select.options.length;
for (i = length-1; i >= 0; i--) {
select.options[i] = null;
}
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How to add text at the end of each line in Vim?
...e file, you can specify them in place of the %.
One way is to do a visual select and then type the :. It will fill in :'<,'> for you, then you type the rest of it (Notice you only need to add s/$/,/)
:'<,'>s/$/,/
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How to put a UserControl into Visual Studio toolBox
...ialog with registered components pops up. in this dialog click "Browse" to select your assembly with the usercontrol you want to use.
PS.
This assembly should be registered before.
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Can Android Studio be used to run standard Java projects?
...id Studio. If you do not have one, create one.
Click File > New Module. Select Java Library and click Next.
Fill in the package name, etc and click Finish. You should now see a Java module inside your Android project.
Add your code to the Java module you've just created.
Click on the drop down to...