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Foreign keys in mongo?
...
You may be interested in using a ORM like Mongoid or MongoMapper.
http://mongoid.org/docs/relations/referenced/1-n.html
In a NoSQL database like MongoDB there are not 'tables' but collections. Documents are grouped inside Collections. You can have any kind of document ...
See changes to a specific file using git
...erstood, it is directory based. This means it gives all the changes of all files on the current directory.
9 Answers
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Pandas percentage of total with groupby
...te the percentage in a simpler way -- just groupby the state_office and divide the sales column by its sum. Copying the beginning of Paul H's answer:
# From Paul H
import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
'...
Read whole ASCII file into C++ std::string [duplicate]
I need to read a whole file into memory and place it in a C++ std::string .
9 Answers
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How to read/write from/to file using Go?
...on my own, but I've been stumped on trying read from and write to ordinary files.
8 Answers
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Update a table using JOIN in SQL Server?
...umn to the aggregate of another column (which violates the principle of avoiding storing redundant data), you can use a CTE (common table expression) - see here and here for more details:
;WITH t2 AS
(
SELECT [key], CalculatedColumn = SUM(some_column)
FROM dbo.table2
GROUP BY [key]
)
UPDA...
sed command with -i option (in-place editing) works fine on Ubuntu but not Mac [duplicate]
...u have installed or other gizmos I've seen suggested. I hope you keep the file under version control (or otherwise backed up) so that you can recover if there's a bug in your sed script. Of course, the .bak file gives you that protection.
– Jonathan Leffler
J...
Reverting single file in SVN to a particular revision
I have a file as shown below in an SVN repo that I would like to revert to a previous version. What is the way to do this in SVN? I want only downgrade this particular file to an older version, not the whole repo.
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Extract directory from path
In my script I need the directory of the file I am working with. For example, the file = "stuff/backup/file.zip" . I need a way to get the string " stuff/backup/ " from the variable $file .
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Is there a way to get the source code from an APK file?
...that I have been working on for the past two months.
All I have is the APK file that is stored in my email from when I sent it to a friend.
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