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MySQL CONCAT returns NULL if any field contain NULL
...es: it returns the first non-NULL value parameter passed to it (or NULL if all parameters are NULL). By passing an empty string as the second parameter, you are guaranteeing it will not return NULL.
– Jo.
Mar 10 '17 at 17:03
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pip broke. how to fix DistributionNotFound error?
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Works great on Mac OS X 10.9 as well. Thanks!
– Anton Babenko
Oct 23 '13 at 16:56
2
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Can't find the 'libpq-fe.h header when trying to install pg gem
...on Rails 3.1 pre version. I like to use PostgreSQL, but the problem is installing the pg gem. It gives me the following error:
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NSLog the method name with Objective-C in iPhone
...happens to be implemented as a C-string (as of the current versions of Mac OS X and the iPhone OS) doesn't mean you should use it in that way, since Apple could change it in an OS update.
– Nick Forge
May 5 '10 at 8:06
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Importing files from different folder
...ere from a search engine, this is not the answer you are looking for. Typically you would structure your files into packages (see other answers) instead of modifying the search path.
By default, you can't. When importing a file, Python only searches the directory that the entry-point script is runn...
Is MonoTouch now banned on the iPhone? [closed]
... C# then it would be violating the license:
...Applications must be originally written in Objective-C, C, C++, or JavaScript as executed by the iPhone OS WebKit engine...
They even hammer it in a little further:
Applications that link to Documented APIs through an intermediary translation or comp...
Bash command to sum a column of numbers [duplicate]
...mn of numbers. I just want a quick one liner that will do something essentially like this:
10 Answers
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How do I get the directory that a program is running from?
... When I see code that looks at /proc part of me dies a little. All the world is not Linux, and even on that one platform /proc should be considered subject to change from version to version, arch to arch, etc.
– asveikau
Jan 28 '10 at 0:29
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How do I get my Python program to sleep for 50 milliseconds?
...rity, CPU load avg, available memory, and a plethora of other factors make all calls imprecise. The busier the system is, the higher the imprecision.
– David
Jan 28 '19 at 18:44
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How to retrieve the current version of a MySQL database management system (DBMS)?
...ile_machine | i686 |
| version_compile_os | pc-linux-gnu |
+-------------------------+------------------------------------------+
5 rows in set (0.04 sec)
MySQL 5.0 Reference Manual (pdf) - Determining Your Current MySQL Version ...