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Finding duplicate values in a SQL table
...T(*) > 1
Simply group on both of the columns.
Note: the older ANSI standard is to have all non-aggregated columns in the GROUP BY but this has changed with the idea of "functional dependency":
In relational database theory, a functional dependency is a constraint between two sets of attrib...
How do multiple clients connect simultaneously to one port, say 80, on a server? [duplicate]
I understand the basics of how ports work. However, what I don't get is how multiple clients can simultaneously connect to say port 80. I know each client has a unique (for their machine) port. Does the server reply back from an available port to the client, and simply state the reply came from 80? ...
Python: List vs Dict for look up table
...f you don't need to associate values, use sets.
Memory
Both dictionaries and sets use hashing and they use much more memory than only for object storage. According to A.M. Kuchling in Beautiful Code, the implementation tries to keep the hash 2/3 full, so you might waste quite some memory.
If you...
Can the Unix list command 'ls' output numerical chmod permissions?
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For creating it as an alias (example below: 'cls' command), use: alias cls="ls -l | awk '{k=0;for(i=0;i<=8;i++)k+=((substr(\$1,i+2,1)~/[rwx]/)*2^(8-i));if(k)printf(\"%0o \",k);print}'"
– danger89
Mar 6 '14 at 16:15
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Difference between Grunt, NPM and Bower ( package.json vs bower.json )
I'm new to using npm and bower, building my first app in emberjs :).
I do have a bit of experience with rails, so I'm familiar with the idea of files for listing dependencies (such as bundler Gemfile)
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How to parse freeform street/postal address out of text, and into components
We do business largely in the United States and are trying to improve user experience by combining all the address fields into a single text area. But there are a few problems:
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Syntax behind sorted(key=lambda: …)
I don't quite understand the syntax behind the sorted() argument:
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vs
... HTML5, they are equivalent. Use the shorter one, it is easier to remember and type. Browser support is fine since it was designed for backwards compatibility.
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How do I clone a subdirectory only of a Git repository?
...it.
Implementing something like this in Git would be a substantial effort and it would mean that the integrity of the clientside repository could no longer be guaranteed. If you are interested, search for discussions on "sparse clone" and "sparse fetch" on the git mailinglist.
In general, the cons...
How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops
How can I use regular expressions in Excel and take advantage of Excel's powerful grid-like setup for data manipulation?
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