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Get pandas.read_csv to read empty values as empty string instead of nan
I'm using the pandas library to read in some CSV data. In my data, certain columns contain strings. The string "nan" is a possible value, as is an empty string. I managed to get pandas to read "nan" as a string, but I can't figure out how to get it not to read an empty value as NaN. Here's sam...
Debug code-first Entity Framework migration codes
I'm using Entity Framework code first in my website and I'm just wondering if there is any way to debug the migration codes. You know, like setting breakpoints and stuff like this.
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How does MongoDB sort records when no sort order is specified?
...ementation detail. Maintaining order is extra overhead for storage engines and MongoDB's API does not mandate predictability outside of an explicit sort() or the special case of fixed-sized capped collections which have associated usage restrictions. For typical workloads it is desirable for the sto...
How to import existing *.sql files in PostgreSQL 8.4?
I am using PostgreSQL 8.4, and I have some *.sql files to import into a database. How can I do so?
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How can I extract a good quality JPEG image from a video file with ffmpeg?
Currently I am using this command to extract the images:
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Implement paging (skip / take) functionality with this query
I have been trying to understand a little bit about how to implement custom paging in SQL, for instance reading articles like this one .
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Can I add a UNIQUE constraint to a PostgreSQL table, after it's already created?
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I needed an answer to this very question and started googling for the docs. Instead of the Postgres documentation, I ran into this topic at StackOverflow. So although it's a good think to reference the official docs, it's also very good to give the answer for future...
What does the “@” symbol do in Powershell?
... in PowerShell to initialise arrays. What exactly does the @ symbol denote and where can I read more about it?
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Haskell Type vs Data Constructor
...m learning Haskell from learnyouahaskell.com . I am having trouble understanding type constructors and data constructors. For example, I don't really understand the difference between this:
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Open files in 'rt' and 'wt' modes
Several times here on SO I've seen people using rt and wt modes for reading and writing files.
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