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If table exists drop table then create it, if it does not exist just create it
...ks for a list of tables or views! DROP TABLE IF EXISTS 'table1', 'table2'; and DROP VIEW IF EXISTS 'view1', 'view2'; PS- What witchcraft did you use to have `s in inline code!?
– Campbeln
Mar 3 '16 at 23:32
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Regex Named Groups in Java
It is my understanding that the java.regex package does not have support for named groups ( http://www.regular-expressions.info/named.html ) so can anyone point me towards a third-party library that does?
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Python time measure function
I want to create a python function to test the time spent in each function and print its name with its time, how i can print the function name and if there is another way to do so please tell me
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What is the meaning of “… …” token? i.e. double ellipsis operator on parameter pack
...mma is purely optional; §8.3.5/4 does say
Where syntactically correct and where “...” is not part of an abstract-declarator, “, ...” is synonymous with “...”.
This is within an abstract-declarator, [edit] but Johannes makes a good point that they are referring to an abstract-decla...
How to throw an exception in C?
...tion (or other notification error form the CPU if there is)(How processor handles the case of division by zero).
Exceptions are defined in C++ and other languages though. Exception handling in C++ is specified in the C++ standard "S.15 Exception handling", there is no equivalent section in the C st...
What's the difference between dynamic (C# 4) and var?
...ing with C# v4, but I couldn't make out the difference between a "dynamic" and "var".
14 Answers
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Python unittest - opposite of assertRaises?
...r test must exit with a failure condition, not an error one. On the other hand, if in running the same code you would raise a KeyError, that would be an error, not a failure. In python - differently than some other languages - Exceptions are routinely used for control flow, this is why we have the e...
private[this] vs private
...t very rich Java background I learnt to close everything (make it private) and open (provide accessors) if necessary. Scala introduces even more strict access modifier. Should I always use it by default? Or should I use it only in some specific cases where I need to explicitly restrict changing fiel...
How do I spool to a CSV formatted file using SQLPLUS?
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Assuming that this is because you are executing a script and writing to a file, you should just "set termout off"
– BobC
Nov 2 '18 at 21:49
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How do I perform the SQL Join equivalent in MongoDB?
...t array field>
}
}
Of course Mongo is not a relational database, and the devs are being careful to recommend specific use cases for $lookup, but at least as of 3.2 doing join is now possible with MongoDB.
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