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How to avoid warning when introducing NAs by coercion
...t know how to avoid getting a warning when using as.numeric to convert a character vector.
4 Answers
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Retrieve the maximum length of a VARCHAR column in SQL Server
...
Use the built-in functions for length and max on the description column:
SELECT MAX(LEN(DESC)) FROM table_name;
Note that if your table is very large, there can be performance issues.
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How do we count rows using older versions of Hibernate (~2009)?
...eturn int and use this form:
int count = ((Long)getSession().createQuery("select count(*) from Book").uniqueResult()).intValue();
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Reliable method to get machine's MAC address in C#
...aces()
where nic.OperationalStatus == OperationalStatus.Up
select nic.GetPhysicalAddress().ToString()
).FirstOrDefault();
Or:
String firstMacAddress = NetworkInterface
.GetAllNetworkInterfaces()
.Where( nic => nic.OperationalStatus == OperationalStatus.Up &&...
How can I use optional parameters in a T-SQL stored procedure?
...ame varchar(25) = null,
@Title varchar(25) = null
AS
BEGIN
SELECT ID, FirstName, LastName, Title
FROM tblUsers
WHERE
(@FirstName IS NULL OR (FirstName = @FirstName))
AND (@LastName IS NULL OR (LastName = @LastName ))
AND (@Tit...
MySQL JOIN the most recent row only?
...
You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
...
XPath - Selecting elements that equal a value
In Xpath, I am wanting to select elements that equal a specific value.
2 Answers
2
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Change default text in input type=“file”?
...e of label for input.
<div>
<label for="files" class="btn">Select Image</label>
<input id="files" style="visibility:hidden;" type="file">
</div>
Below is the code to fetch name of the uploaded file
$("#files").change(function() {
filename = this.files[...
How do I submit disabled input in ASP.NET MVC?
...l be submitted to the server while still being non-editable by the user. A SELECT tag is an exception though.
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Is there a Max function in SQL Server that takes two values like Math.Max in .NET?
...
return isnull(@val2,@val1)
end
... and you would call it like so ...
SELECT o.OrderId, dbo.InlineMax(o.NegotiatedPrice, o.SuggestedPrice)
FROM Order o
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