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What's the difference(s) between .ToList(), .AsEnumerable(), AsQueryable()?
...y we would typically write something like
var query = context.Observations.Select(o => o.Id)
.AsEnumerable().Select(x => MySuperSmartMethod(x))
ToList – which converts an IEnumerable<T> to a List<T> – is often used for this purpose as well. The advantage of...
Better techniques for trimming leading zeros in SQL Server?
...
Why don't you just cast the value to INTEGER and then back to VARCHAR?
SELECT CAST(CAST('000000000' AS INTEGER) AS VARCHAR)
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0
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MySQL offset infinite rows
...er. This statement
retrieves all rows from the 96th row
to the last:
SELECT * FROM tbl LIMIT 95, 18446744073709551615;
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PostgreSQL query to return results as a comma separated list
Let say you have a SELECT id from table query (the real case is a complex query) that does return you several results.
5 ...
How to create an installer for a .net Windows Service using Visual Studio
...out dragging stuff from the toolbox.
Then right click on the gray area and select add installer. This will add an installer project file to your project.
Then you will have 2 components on the design view of the ProjectInstaller.cs (serviceProcessInstaller1 and serviceInstaller1). You should then se...
How to get a user's client IP address in ASP.NET?
...TE_ADDR")
Else
Dim ipArray As String() = sIPAddress.Split(New [Char]() {","c})
Return ipArray(0)
End If
End Function
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MySQL Query GROUP BY day / month / year
... for added clarity in some cases such as where records span several years. SELECT COUNT(event_id), DATE_FORMAT(event_start, '%Y/%m')
– Ric
Apr 4 '13 at 10:25
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SQL statement to get column type
...
Using SQL Server:
SELECT DATA_TYPE
FROM INFORMATION_SCHEMA.COLUMNS
WHERE
TABLE_NAME = 'yourTableName' AND
COLUMN_NAME = 'yourColumnName'
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Count(*) vs Count(1) - SQL Server
...
The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...
jQuery - getting custom attribute from selected option
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You're adding the event handler to the <select> element.
Therefore, $(this) will be the dropdown itself, not the selected <option>.
You need to find the selected <option>, like this:
var option = $('option:selected', this).attr('mytag');
...