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How to use NULL or empty string in SQL
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my best solution :
WHERE
COALESCE(char_length(fieldValue), 0) = 0
COALESCE returns the first non-null expr in the expression list().
if the fieldValue is null or empty string then: we will return the second element then...
What is the canonical way to check for errors using the CUDA runtime API?
...stError , cudaPeekAtLastError , and cudaGetErrorString , but what is the best way to put these together to reliably catch and report errors without requiring lots of extra code?
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Compare two objects and find the differences [duplicate]
what is the best way to compare two objects and find the differences?
2 Answers
2
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Algorithm for creating a school timetable
...pert systems aside, this is a field where genetic algorithms are among the best bets. The difficulty does not lie in solving the problem, not only. The difficulty also lies in stating the problem and its constraints.
– Stefano Borini
Feb 2 '10 at 10:53
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Redis strings vs Redis hashes to represent JSON: efficiency?
...red","age":25}'
SADD users {id}
Generally speaking, this is probably the best method in most cases. If there are a lot of fields in the Object, your Objects are not nested with other Objects, and you tend to only access a small subset of fields at a time, it might be better to go with option 2.
A...
How do I clear the terminal screen in Haskell?
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@Peter my best guess is it's because they don't think it's a haskell solution (rightfully so; it only works in GHCi), it doesn't work for them (shell-dependent) or they just consider ZachS' answer a better one. :! cls is plenty suffici...
MySQL combine two columns into one column
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I have used this way and Its a best forever. In this code null also handled
SELECT Title,
FirstName,
lastName,
ISNULL(Title,'') + ' ' + ISNULL(FirstName,'') + ' ' + ISNULL(LastName,'') as FullName
FROM Customer
Try this...
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How is Node.js inherently faster when it still relies on Threads internally?
...lso be wasting main heap memory. Now, for Java, wasting heap is the first, best, way to screw up the system's performance, because efficient garbage collection (currently, this might change with G1, but it seems that the jury is still out on that point as of early 2013 at least) depends on having lo...
Catching an exception while using a Python 'with' statement
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The best "Pythonic" way to do this, exploiting the with statement, is listed as Example #6 in PEP 343, which gives the background of the statement.
@contextmanager
def opened_w_error(filename, mode="r"):
try:
f = ope...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
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Enlightening answer. This is undoubtedly the best answer here. It gave me rationale of introducing the new value categories and what happened prior.
– Nikos
Sep 24 '18 at 2:37
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