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SQL Server: Difference between PARTITION BY and GROUP BY
I've been using GROUP BY for all types of aggregate queries over the years. Recently, I've been reverse-engineering some code that uses PARTITION BY to perform aggregations. In reading through all the documentation I can find about PARTITION BY , it sounds a lot like GROUP BY , maybe with a ...
Is a one column table good design? [closed]
It it ok to have a table with just one column? I know it isn't technically illegal, but is it considered poor design?
15 A...
Postgresql: password authentication failed for user “postgres”
I have installed PostgreSQL 8.4, Postgres client and Pgadmin 3. Authentication failed for user "postgres" for both console client and Pgadmin. I have typed user as "postgres" and password "postgres", because it worked before. But now authentication is failed. I did it before a couple of times withou...
Is there a float input type in HTML5?
According to html5.org , the "number" input type's "value attribute, if specified and not empty, must have a value that is a valid floating point number."
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ssh “permissions are too open” error
... 400 is too low as that makes it non-writable by your own user. 600 is actually recommended as it allows owner read-write not just read.
– jfreak53
Jul 9 '13 at 23:55
8
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Calculating Pearson correlation and significance in Python
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Help on function pearsonr in module scipy.stats.stats:
pearsonr(x, y)
Calculates a Pearson correlation coefficient and the p-value for testing
non-correlation.
The Pearson correlation coefficient measures the linear relationship
between two datasets. Strictly speaking, Pearson's correlation ...
Doing HTTP requests FROM Laravel to an external API
... an object from an API with a HTTP (eg, jQuery's AJAX) request to an external api. How do I start? I did research on Mr Google but I can't find anything helping.
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How to convert byte array to string and vice versa?
...rt a byte array to string in Android, but my byte array contains negative values.
22 Answers
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Check if value exists in Postgres array
Using Postgres 9.0, I need a way to test if a value exists in a given array. So far I came up with something like this:
7 A...
Weird Integer boxing in Java
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The true line is actually guaranteed by the language specification. From section 5.1.7:
If the value p being boxed is true,
false, a byte, a char in the range
\u0000 to \u007f, or an int or short
number between -128 and 127, then let
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