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Linux command (like cat) to read a specified quantity of characters
Is there a command like cat in linux which can return a specified quantity of characters from a file?
9 Answers
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NULL values inside NOT IN clause
...t I thought were identical queries one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the con...
Performance surprise with “as” and nullable types
...'m just revising chapter 4 of C# in Depth which deals with nullable types, and I'm adding a section about using the "as" operator, which allows you to write:
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What is the benefit of using Fragments in Android, rather than Views?
When developing for Android , you can set your target (or minimum) sdk to 4 (API 1.6) and add the android compatibility package (v4) to add support for Fragments . Yesterday I did this and successfully implemented Fragments to visualize data from a custom class.
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How can I read command line parameters from an R script?
I've got a R script for which I'd like to be able to supply several command-line parameters (rather than hardcode parameter values in the code itself). The script runs on Windows.
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boost::flat_map and its performance compared to map and unordered_map
...haven't been able to find any performance comparisons. How does it compare and what are the best use cases for it?
2 Answer...
How to set HTTP headers (for cache-control)?
...ive CACHE-CONTROL:NO-CACHE indicates cached information should not be used
and instead requests should be forwarded to the origin server. This directive has the same semantics as the PRAGMA:NO-CACHE.
Clients SHOULD include both PRAGMA: NO-CACHE and CACHE-CONTROL: NO-CACHE when a no-cache request is...
How to get users to read error messages?
...ind yourself at a high risk that users will not read your carefully worded and enlightening error messages, but just click on the first button available with a shrug of frustration.
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How do I convert a column of text URLs into active hyperlinks in Excel?
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If you don't want to make a macro and as long as you don't mind an additional column, then just create a new column alongside your column of URLs.
In the new column type in the formula =HYPERLINK(A1) (replacing A1 with whatever cell you are interested in). T...
Should I use pt or px?
What is the difference between pt and px in CSS? Which one should I use and why?
5 Answers
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