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PostgreSQL delete with inner join
...
DELETE
FROM m_productprice B
USING m_product C
WHERE B.m_product_id = C.m_product_id AND
C.upc = '7094' AND
B.m_pricelist_version_id='1000020';
or
DELETE
FROM m_productprice
WHERE m_pricelist_version_id='1000020...
What's the difference between & and && in MATLAB?
What is the difference between the & and && logical operators in MATLAB?
7 Answers
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What does “coalgebra” mean in the context of programming?
I have heard the term "coalgebras" several times in functional programming and PLT circles, especially when the discussion is about objects, comonads, lenses, and such. Googling this term gives pages that give mathematical description of these structures which is pretty much incomprehensible to me. ...
Python Dictionary to URL Parameters
...ictionary to a string for use as URL parameters. I am sure that there is a better, more Pythonic way of doing this. What is it?
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Callback functions in Java
Is there a way to pass a call back function in a Java method?
17 Answers
17
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In Javascript, how to conditionally add a member to an object?
I would like to create an object with a member added conditionally.
The simple approach is:
22 Answers
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Difference between declaring variables before or in loop?
I have always wondered if, in general, declaring a throw-away variable before a loop, as opposed to repeatedly inside the loop, makes any (performance) difference?
A (quite pointless) example in Java:
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Get records with max value for each group of grouped SQL results
... a super-simple way to do this in mysql:
select *
from (select * from mytable order by `Group`, age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. The solution is to first order the ...
How to implement a queue with three stacks?
I came across this question in an algorithms book ( Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne).
5 Answ...
Append an object to a list in R in amortized constant time, O(1)?
If I have some R list mylist , you can append an item obj to it like so:
17 Answers
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