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SQL select only rows with max value on a column [duplicate]
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At first glance...
All you need is a GROUP BY clause with the MAX aggregate function:
SELECT id, MAX(rev)
FROM YourTable
GROUP BY id
It's never that simple, is it?
I just noticed you need the content column as well.
This is a very common q...
Replace specific characters within strings
... fixed=TRUE prevents R from using regular expressions, which allow more flexible pattern matching but take time to compute. If all that's needed is removing a single constant string "e", they aren't necessary.
– mm689
Oct 31 '16 at 19:16
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Big-O summary for Java Collections Framework implementations? [closed]
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Collections Overview has a nice summary table.
Annotated Outline lists all of the implementations on one page.
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How to trace the path in a Breadth-First Search?
... found
if node == end:
return path
# enumerate all adjacent nodes, construct a new path and push it into the queue
for adjacent in graph.get(node, []):
new_path = list(path)
new_path.append(adjacent)
queue.append(new_path)
prin...
Quit and restart a clean R session from within R?
... to be included in R script to restart R session? (the reason being I want all packages to be detached)
– Heisenberg
Oct 19 '14 at 20:04
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How do I provide a username and password when running “git clone git@remote.git”?
...nfiguration of the remote server.
Use ssh-agent to avoid typing passwords all the time
If you don't want to type your ssh password all the time, the typical solution is to generate a public/private key pair, put the public key in your ~/.ssh/authorized_keys file on the remote server, and load your...
Can you have multiple $(document).ready(function(){ … }); sections?
If I have a lot of functions on startup do they all have to be under one single:
11 Answers
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How to limit setAccessible to only “legitimate” uses?
...hat kind of an architecture.
If you're distributing a software component called foo.jar to the people of the world, you're completely at their mercy anyway. They could modify the class definitions inside your .jar (through reverse engineering or direct bytecode manipulation). They could run your co...
How to find keys of a hash?
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There is function in modern JavaScript (ECMAScript 5) called Object.keys performing this operation:
var obj = { "a" : 1, "b" : 2, "c" : 3};
alert(Object.keys(obj)); // will output ["a", "b", "c"]
Compatibility details can be found here.
On the Mozilla site there is also a sn...
Select top 10 records for each category
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If you really just want the top 10, change it to RowNumber() instead of Rank(). No ties then.
– Mike L
Oct 7 '08 at 3:26
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