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Style child element when hover on parent
...answered Aug 27 '11 at 21:16
jtbandesjtbandes
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How to make a chain of function decorators?
...dule from PyPI: they preserve certain important metadata (such as __name__ and, speaking about the decorator package, function signature).
– Marius Gedminas
Mar 11 '11 at 2:30
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How to specify mapping rule when names of properties differ
I am a newbie to the Automapper framework. I have a domain class and a DTO class as follows:
4 Answers
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Java 8 NullPointerException in Collectors.toMap
...ws a NullPointerException if one of the values is 'null'. I don't understand this behaviour, maps can contain null pointers as value without any problems. Is there a good reason why values cannot be null for Collectors.toMap ?
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Get records with max value for each group of grouped SQL results
...alue for.
You avoid complicated subqueries that try to find the max() etc, and also the problems of returning multiple rows when there are more than one with the same maximum value (as the other answers would do)
Note: This is a mysql-only solution. All other databases I know will throw an SQL synta...
How to print a date in a regular format?
...r() function. It is most of the time the most common human readable format and is used to ease display. So str(datetime.datetime(2008, 11, 22, 19, 53, 42)) gives you '2008-11-22 19:53:42'.
The alternative representation that is used to represent the object nature (as a data). It can be get using th...
Docker build “Could not resolve 'archive.ubuntu.com'” apt-get fails to install anything
...pears after a long time
Server: 8.8.8.8
Address 1: 8.8.8.8
If the command appears to hang, but eventually spits out the error "can't resolve 'google.com'", then you have the same problem as me.
The nslookup command queries the DNS server 8.8.8.8 in order to turn the text address of 'google.com...
Pandas aggregate count distinct
Let's say I have a log of user activity and I want to generate a report of total duration and the number of unique users per day.
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How can I alter a primary key constraint using SQL syntax?
...rimary key constraint name, use query found here to look it up (or look up and drop all at once). http://stackoverflow.com/a/13948609/945875
– Justin
Dec 19 '13 at 20:06
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Should I declare Jackson's ObjectMapper as a static field?
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Yes, that is safe and recommended.
The only caveat from the page you referred is that you can't be modifying configuration of the mapper once it is shared; but you are not changing configuration so that is fine. If you did need to change conf...