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MySQL “Group By” and “Order By”
...
A simple solution is to wrap the query into a subselect with the ORDER statement first and applying the GROUP BY later:
SELECT * FROM (
SELECT `timestamp`, `fromEmail`, `subject`
FROM `incomingEmails`
ORDER BY `timestamp` DESC
) AS tmp_table GROUP BY LOWER(`fromEmail`)
This ...
Couldn't connect to server 127.0.0.1:27017
...cause the mongod process it's down, you must to run the commands bellow in order to get up the mongod process:
~$ sudo service mongodb stop
~$ sudo rm /var/lib/mongodb/mongod.lock
~$ sudo mongod --repair --dbpath /var/lib/mongodb
~$ sudo mongod --fork --logpath /var/lib/mongodb/mongodb.log --dbp...
What is the JSF resource library for and how should it be used?
...niFaces CombinedResourceHander had to introduce a reflection-based hack in order to get it to work anyway with RichFaces resources.
Your own webapp
Your own webapp does not necessarily need a resource library. You'd best just omit it.
<h:outputStylesheet name="css/style.css" />
<h:outpu...
Rails: Default sort order for a rails model?
I would like to specify a default sort order in my model.
3 Answers
3
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How to implement LIMIT with SQL Server?
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Starting SQL SERVER 2005, you can do this...
USE AdventureWorks;
GO
WITH OrderedOrders 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 someth...
Sort JavaScript object by key
...6/ES2015 spec has been published.
See the section on property iteration order in Exploring ES6 by Axel Rauschmayer:
All methods that iterate over property keys do so in the same order:
First all Array indices, sorted numerically.
Then all string keys (that are not indices), in the o...
Java Set retain order?
Does a Java Set retain order? A method is returning a Set to me and supposedly the data is ordered but iterating over the Set, the data is unordered. Is there a better way to manage this? Does the method need to be changed to return something other than a Set?
...
How to get cumulative sum
...om @t t1
inner join @t t2 on t1.id >= t2.id
group by t1.id, t1.SomeNumt
order by t1.id
SQL Fiddle example
Output
| ID | SOMENUMT | SUM |
-----------------------
| 1 | 10 | 10 |
| 2 | 12 | 22 |
| 3 | 3 | 25 |
| 4 | 15 | 40 |
| 5 | 23 | 63 |
Edit: this...
How to set a Default Route (To an Area) in MVC
...
);
}
in Application_Start(), make sure to use the following order;
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
RegisterRoutes(RouteTable.Routes);
}
in you area registration, use
public override void RegisterArea(AreaReg...
Combine two data frames by rows (rbind) when they have different sets of columns
...=6:10, b=16:20, c = letters[8:12])
Two data.frames, alter originals
In order to retain all columns from both data.frames in an rbind (and allow the function to work without resulting in an error), you add NA columns to each data.frame with the appropriate missing names filled in using setdiff.
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