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Which is the fastest algorithm to find prime numbers?
...e needed in code, perhaps when you need to
dynamically find a prime hash table size within certain ranges. If N
is something on the order of 2^30, do you really want to do 30000
division tests to search for any factors? Obviously not.
The common practical solution to this problem is a sim...
Hibernate error - QuerySyntaxException: users is not mapped [from users]
I'm trying to get a list of all the users from "users" table and I get the following error:
18 Answers
...
SQL WHERE ID IN (id1, id2, …, idn)
...DMS and so you would need us use @Ed Guiness's solution but here temporary tables do differ between RDBMS. (Effectively for complex problems you can't use just pure standard SQL)
– mmmmmm
Apr 27 '11 at 12:27
...
How to copy data from one table to another new table in MySQL?
I want to copy data from one table to another in MySQL.
11 Answers
11
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Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
...o use query hints, restructure the query, update statistics, use temporary tables, add indexes, and so on to get better performance.
As for your question. The performance of CTEs and subqueries should, in theory, be the same since both provide the same information to the query optimizer. One diff...
Use numpy array in shared memory for multiprocessing
... function G inside of F which references V?
– Coffee_Table
Oct 27 '17 at 1:38
5
Warning: This ans...
How do I move a table into a schema in T-SQL
I want to move a table into a specific Schema using T-SQL? I am using SQL Server 2008.
2 Answers
...
Can hash tables really be O(1)?
It seems to be common knowledge that hash tables can achieve O(1), but that has never made sense to me. Can someone please explain it? Here are two situations that come to mind:
...
How to get rid of punctuation using NLTK tokenizer?
...slate(None, string.punctuation)
Or for unicode:
import string
translate_table = dict((ord(char), None) for char in string.punctuation)
s.translate(translate_table)
and then use this string in your tokenizer.
P.S. string module have some other sets of elements that can be removed (like digit...
Is there a way to get a collection of all the Models in your Rails app?
...
ActiveRecord::Base.connection.tables.map do |model|
model.capitalize.singularize.camelize
end
will return
["Article", "MenuItem", "Post", "ZebraStripePerson"]
Additional information If you want to call a method on the object name without model:stri...