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Postgres: Distinct but only for one column
...ame. If you want to control which of the rows will be returned you need to order:
select distinct on (name)
name, col1, col2
from names
order by name, col1
Will return the first row when ordered by col1.
distinct on:
SELECT DISTINCT ON ( expression [, ...] ) keeps only the first row of each se...
What is Serialization?
...database, or a file. Its main purpose is to save the state of an object in order to be able to recreate it when needed. The reverse process is called deserialization.
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This illustration shows the overall process of serialization
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Through serialization, a developer can...
How do I adjust the anchor point of a CALayer, when Auto Layout is being used?
...of the View when first called and reuses that Position in further calls in order to place the View accordingly. This overwrites the Autolayout Code in that sense, that it takes place after [super layoutSubviews]; which contains autolayout Code.
Like that there is no longer any need to avoid Autolay...
Order data frame rows according to vector with specific order
Is there an easier way to ensure that a data frame's rows are ordered according to a "target" vector as the one I implemented in the short example below?
...
How do I restart a WPF application? [duplicate]
....Current.Shutdown();
System.Windows.Forms.Application.Restart();
In this order worked for me, the other way around just started another instance of the app.
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Unable to start debugging because the object invoked has disconnected from its clients
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MySQL “Group By” and “Order By”
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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 ...
Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
...ject_id = OBJECT_ID('YourTableName')
Collations are needed and used when ordering and comparing strings. It's generally a good idea to have a single, unique collation used throughout your database - don't use different collations within a single table or database - you're only asking for trouble.....
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...