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Get top 1 row of each group
...)
SELECT *
FROM cte
WHERE rn = 1
If you expect 2 entries per day, then this will arbitrarily pick one. To get both entries for a day, use DENSE_RANK instead
As for normalised or not, it depends if you want to:
maintain status in 2 places
preserve status history
...
As it stands, you preserve ...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
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Notice: Undefined variable
From the vast wisdom of the PHP Manual:
Relying on the default value of an uninitialized variable is problematic in the case of including one file into another which uses the same variable name. It is also a major security risk with reg...
How to detect a textbox's content has changed
...generate letters, like the arrow keys. I thought of two methods of doing this using the keyup event:
15 Answers
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Manual deployment vs. Amazon Elastic Beanstalk
...are definitely advantages.
However, you have to kind of think about it this way: In a true Platform as a Service (PAAS), the goal is to separate the application from the platform. As a developer, you only worry about your application. The platform is "rented" to you. The platform "instances" are a...
Indenting #defines
...d to always be placed in the first column.
Pre-ANSI C compilers are non-existent these days. Use which ever style (space before "#" or space between "#" and the identifier) you prefer.
http://www.delorie.com/gnu/docs/gcc/cpp_48.html
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In C# what is the difference between ToUpper() and ToUpperInvariant()?
In C#, what is the difference between ToUpper() and ToUpperInvariant() ?
6 Answers
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Difference between Fact table and Dimension table?
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This is to answer the part:
I was trying to understand whether dimension tables can be fact table
as well or not?
The short answer (INMO) is No.That is because the 2 types of tables are created for different reasons. H...
Difference between style = “position:absolute” and style = “position:relative”
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Absolute positioning means that the element is taken completely out of the normal flow of the page layout. As far as the rest of the elements on the page are concerned, the absolutely positioned element simply doesn't exist. The element itself is then drawn separately,...
How to compare two floating point numbers in Bash?
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More conveniently
This can be done more conveniently using Bash's numeric context:
if (( $(echo "$num1 > $num2" |bc -l) )); then
…
fi
Explanation
Piping through the basic calculator command bc returns either 1 or 0.
The option -l is ...
Overriding the java equals() method - not working?
I ran into an interesting (and very frustrating) issue with the equals() method today which caused what I thought to be a well tested class to crash and cause a bug that took me a very long time to track down.
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