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How to do an INNER JOIN on multiple columns
I'm working on a homework project and I'm supposed to perform a database query which finds flights either by the city name or the airport code, but the flights table only contains the airport codes so if I want to search by city I have to join on the airports table.
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When should I use double instead of decimal?
...ing to offer at least as great precision (someone correct me if I'm wrong) and definitely greater speed for arbitrary real numbers. The simple conclusion is: when considering which to use, always use double unless you need the base 10 accuracy that decimal offers.
Edit:
Regarding your additional q...
Why is there no SortedList in Java?
In Java there are the SortedSet and SortedMap interfaces. Both belong to the Java Collections framework and provide a sorted way to access the elements.
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Can existing virtualenv be upgraded gracefully?
I have a virtualenv created for Python 2.5 and want to "upgrade" it to Python 2.6.
5 Answers
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How to create a self-signed certificate for a domain name for development?
...tificate feature, you cannot set the common name (CN) for the certificate, and therefore cannot create a certificate bound to your choice of subdomain.
One way around the problem is to use makecert.exe, which is bundled with the .Net 2.0 SDK. On my server it's at:
C:\Program Files\Microsoft.Net\SD...
How to insert a newline in front of a pattern?
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This works in bash and zsh, tested on Linux and OS X:
sed 's/regexp/\'$'\n/g'
In general, for $ followed by a string literal in single quotes bash performs C-style backslash substitution, e.g. $'\t' is translated to a literal tab. Plus, sed ...
How to check if an array field contains a unique value or another array in MongoDB?
...n the help: mongodb.org/display/DOCS/…
– Scott Hernandez
Mar 20 '11 at 4:31
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for the $all does...
How to convert JSON to CSV format and store in a variable
...ead it. Is there a way to convert this data using JavaScript in CSV format and save it in JavaScript file?
16 Answers
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Foreign key constraints: When to use ON UPDATE and ON DELETE
...ma using MySQL Workbench, which is pretty cool because you can do diagrams and it converts them :P
3 Answers
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Android Studio/Intellij Idea: “Table of Contents” for a class
I have been messing around with Android Studio and so far I like most of what I have seen. One thing that has been annoying me though is this lack of "Table of Contents" for a class. I apologize for not knowing exactly what to call it. But what I am referring to is the dropdown menu in eclipse that ...