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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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What's the difference between identifying and non-identifying relationships?
...t been able to fully grasp the differences. Can you describe both concepts and use real world examples?
15 Answers
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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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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...
How to change the CHARACTER SET (and COLLATION) throughout a database?
... table (Mysql). He set it up with Latin collation, when it should be UTF8, and now I have issues. Every record with Chinese and Japan character turn to ??? character.
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How many concurrent requests does a single Flask process receive?
I'm building an app with Flask, but I don't know much about WSGI and it's HTTP base, Werkzeug. When I start serving a Flask application with gunicorn and 4 worker processes, does this mean that I can handle 4 concurrent requests?
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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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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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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...
Warning - Build path specifies execution environment J2SE-1.4
...er you do [Alt][F5] to update maven config all such manual tweaks get lots and the warning comes back. See bugs.eclipse.org/bugs/show_bug.cgi?id=376619
– Jörg
Oct 31 '16 at 16:22
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