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How to match any non white space character except a particular one?
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When is ^ interpreted as negation and when as line beginning ? In that respect, why this wont match a line starting with number of white spaces $0~/\s*^\s/
– Alexander Cska
Mar 26 '19 at 21:43
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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...
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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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:
2 Answers
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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...
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?
5 Answers
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AngularJS directive with default options
I'm just starting with angularjs, and am working on converting a few old JQuery plugins to Angular directives. I'd like to define a set of default options for my (element) directive, which can be overridden by specifying the option value in an attribute.
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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?
5 Answers
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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...
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.
4 Answers
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