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stringstream, string, and char* conversion confusion
...ring around, and it's destroyed, and thus your const char * is pointing to free'd memory.
Your statement string str(ss.str()); means that the temporary is used in the constructor for the string variable str that you've put on the local stack, and that stays around as long as you'd expect: until the...
What are the use cases for selecting CHAR over VARCHAR in SQL?
...t could be used. In UTF8 that's 3 bytes per character. For varchar, it's free to use 1-3 bytes per character as needed. This is in the MySQL manual: dev.mysql.com/doc/refman/5.0/en/charset-unicode-utf8.html
– Gavin Towey
Mar 27 '14 at 2:14
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Check if table exists in SQL Server
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For queries like this it is always best to use an INFORMATION_SCHEMA view. These views are (mostly) standard across many different databases and rarely change from version to version.
To check if a table exists use:
IF (EXISTS (SELECT *
FROM INFORMATION_...
How to debug apk signed for release?
... the sources. if you are doing both and it still does not work, share more info and I may try to help
– sandalone
Jun 19 '16 at 20:14
2
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What does it mean if a Python object is “subscriptable” or not?
...lse: # make sure we always return a list, no matter what!
logging.info("Something didn't happen; return empty list")
return []
Of course, what you put in the else: branch depends on your use case. Perhaps you should raise an exception when something_happens() fails, to make it mor...
Eclipse - java.lang.ClassNotFoundException
...o me, but if it doesnt work, please try the others.
here and here is some info
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How to get overall CPU usage (e.g. 57%) on Linux [closed]
... 0.00 0.01 0.00 0.00 97.03
Then some cutor grepto parse the info you need:
mpstat | grep -A 5 "%idle" | tail -n 1 | awk -F " " '{print 100 - $ 12}'a
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What is the Haskell response to Node.js?
... green thread, they are of course cheaper than OS threads but they are not free. Creating 100.000 of them uses approx. 350 MB of memory and take some time. Try 100.000 connections with node.js. No problem at all . It would be magic if it were not faster since ghc uses epoll under the hood so they ca...
How can I convert spaces to tabs in Vim or Linux?
...... Than you realize you probably want a tab to be 4 spaces. Now with that info, you do:
:set ts=4
:set noet
:%retab!
There is a problem here! This sequence of commands will look for all your text, not only spaces in the begin of the line. That mean a string like: "Hey,␣this␣␣␣␣is␣4␣s...
What is the difference between sigaction and signal?
...n", signal);
break;
}
// DO PROGRAM CLEANUP HERE, such as freeing memory, closing files, etc.
exit(signal);
}
/// @brief Set a new signal handler action for a given signal
/// @details Only update the signals with our custom handler if they are NOT set to "signal igno...