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How to use count and group by at the same select statement
I have an sql select query that has a group by.
I want to count all the records after the group by statement.
Is there a way for this directly from sql?
For example, having a table with users I want to select the different towns and the total number of users
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Applying function with multiple arguments to create a new pandas column
I want to create a new column in a pandas data frame by applying a function to two existing columns. Following this answer I've been able to create a new column when I only need one column as an argument:
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How to return a part of an array in Ruby?
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Yes, Ruby has very similar array-slicing syntax to Python. Here is the ri documentation for the array index method:
--------------------------------------------------------------- Array#[]
array[index] -> obj or nil
array[start, length] ...
PHP Timestamp into DateTime
Do you know how I can convert this to a strtotime, or a similar type of value to pass into the DateTime object?
4 Answer...
Error in plot.new() : figure margins too large in R
I'm new to R but I've made numerous correlation plots with smaller data sets. However, when I try to plot a large dataset (2gb+), I can produce the plot just fine, but the legend doesn't show up. Any advice? or alternatives?
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How to drop unique in MySQL?
I want to drop the unique key on email ,how?
10 Answers
10
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Difference between Rebuild and Clean + Build in Visual Studio
...ng of events can become significant when inter-project dependencies come into play.
All three actions correspond to MSBuild targets. So a project can override the Rebuild action to do something completely different.
share
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LINQ OrderBy versus ThenBy
...);
Note how you can use the same name each time. This is also equivalent to:
tmp = from o in invoices.InvoiceCollection
orderby o.InvoiceOwner.LastName,
o.InvoiceOwner.FirstName,
o.InvoiceID
select o;
If you call OrderBy multiple times, it will effectivel...
JS Client-Side Exif Orientation: Rotate and Mirror JPEG Images
Digital camera photos are often saved as JPEG with an EXIF "orientation" tag. To display correctly, images need to be rotated/mirrored depending on which orientation is set, but browsers ignore this information rendering the image. Even in large commercial web apps, support for EXIF orientation can ...
List of zeros in python [duplicate]
How can I create a list which contains only zeros? I want to be able to create a zeros list for each int in range(10)
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