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Linear Regression and group by in R
...to a vector. That does not seem very R-like, however. In SAS I would do a 'by' statement and in SQL I would do a 'group by'. What's the R way of doing this?
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Local Storage vs Cookies
I want to reduce load times on my websites by moving all cookies into local storage since they seem to have the same functionality. Are there any pros/cons (especially performance-wise) in using local storage to replace cookie functionality except for the obvious compatibility issues?
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Get JSF managed bean by name in any Servlet related class
...vlet (for AJAX/JSON) in which I would like to reference my @ManagedBeans by name. I'm hoping to map:
6 Answers
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MySQL - Using COUNT(*) in the WHERE clause
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try this;
select gid
from `gd`
group by gid
having count(*) > 10
order by lastupdated desc
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How to implement LIMIT with SQL Server?
...ders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrders
WHERE RowNumber BETWEEN 10 AND 20;
or something like this for 2000 and below versions...
SELECT TOP 10 * FROM (SELECT TOP 20 FR...
How do I delete rows in a data frame?
...d keep the complement of that set.
In R, the complement of a set is given by the '-' operator.
So, assuming the data.frame is called myData:
myData[-c(2, 4, 6), ] # notice the -
Of course, don't forget to "reassign" myData if you wanted to drop those rows entirely---otherwise, R just prints t...
MySql : Grant read only options?
...ng" from tables and views is the SELECT privilege. If that's what you mean by "all read" then yes:
GRANT SELECT ON *.* TO 'username'@'host_or_wildcard' IDENTIFIED BY 'password';
However, it sounds like you mean an ability to "see" everything, to "look but not touch." So, here are the other kinds...
C# string reference type?
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The reference to the string is passed by value. There's a big difference between passing a reference by value and passing an object by reference. It's unfortunate that the word "reference" is used in both cases.
If you do pass the string reference by reference, ...
Sort Dictionary by keys
...st to provide a solution for getting an array of (key, value) pairs sorted by keys. Thanks for the comment.
– Ivica M.
Dec 24 '14 at 18:27
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Select where count of one field is greater than one
...b.table
HAVING COUNT(someField) > 1
Ideally, there should be a GROUP BY defined for proper valuation in the HAVING clause, but MySQL does allow hidden columns from the GROUP BY...
Is this in preparation for a unique constraint on someField? Looks like it should be...
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