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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...
Joining three tables using MySQL
I have three tables named
8 Answers
8
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how to check if object already exists in a list
...eeds of the specific situation. For example, the dictionary approach would be quite good assuming:
The list is relatively stable (not a lot of inserts/deletions, which dictionaries are not optimized for)
The list is quite large (otherwise the overhead of the dictionary is pointless).
If the above ...
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?
...
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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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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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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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 ...