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what is the difference between GROUP BY and ORDER BY in sql
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ORDER BY alters the order in which items are returned.
GROUP BY will aggregate records by the specified columns which allows you to perform aggregation functions on non-grouped columns (such as SUM, COUNT, AVG, etc).
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Should I use PATCH or PUT in my REST API?
...d is the correct choice here as you're updating an existing resource - the group ID. PUT should only be used if you're replacing a resource in its entirety.
Further information on partial resource modification is available in RFC 5789. Specifically, the PUT method is described as follows:
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Is it possible to GROUP BY multiple columns using MySQL?
Is it possible to GROUP BY more than one column in a MySQL SELECT query? For example:
7 Answers
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Get records with max value for each group of grouped SQL results
How do you get the rows that contain the max value for each grouped set?
17 Answers
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Is there a command to list all Unix group names? [closed]
I know there is the /etc/group file that lists all users groups.
3 Answers
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Named capturing groups in JavaScript regex?
As far as I know there is no such thing as named capturing groups in JavaScript. What is the alternative way to get similar functionality?
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ORA-00979 not a group by expression
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You must put all columns of the SELECT in the GROUP BY or use functions on them which compress the results to a single value (like MIN, MAX or SUM).
A simple example to understand why this happens: Imagine you have a database like this:
FOO BAR
0 A
0 B
and you ru...
LINQ with groupby and count
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After calling GroupBy, you get a series of groups IEnumerable<Grouping>, where each Grouping itself exposes the Key used to create the group and also is an IEnumerable<T> of whatever items are in your original data set. You jus...
How to get the groups of a user in Active Directory? (c#, asp.net)
I use this code to get the groups of the current user. But I want to manually give the user and then get his groups. How can I do this?
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How to select the row with the maximum value in each group
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Here's a data.table solution:
require(data.table) ## 1.9.2
group <- as.data.table(group)
If you want to keep all the entries corresponding to max values of pt within each group:
group[group[, .I[pt == max(pt)], by=Subject]$V1]
# Subject pt Event
# 1: 1 5 2
# 2: ...