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Case in Select Statement
...imple CASE expression
Within a SELECT statement, a simple CASE expression allows for only an equality check; no other comparisons are made. The following example uses the CASE expression to change the display of product line categories to make them more understandable.
USE AdventureWorks2012;
GO
S...
Why doesn't println! work in Rust unit tests?
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@Nashenas, the option is called nocapture, not no-capture.
– Vladimir Matveev
Jul 16 '15 at 5:21
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How do I get Flask to run on port 80?
...roxy HTTP traffic through apache2 to Flask.
This way, apache2 can handle all your static files (which it's very good at - much better than the debug server built into Flask) and act as a reverse proxy for your dynamic content, passing those requests to Flask.
Here's a link to the official documen...
Is a Python dictionary an example of a hash table?
One of the basic data structures in Python is the dictionary, which allows one to record "keys" for looking up "values" of any type. Is this implemented internally as a hash table? If not, what is it?
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Which data type for latitude and longitude?
...y) which can be your lat / long. Occupies 16 bytes: 2 float8 numbers internally.
Or make it two columns of type float (= float8 or double precision). 8 bytes each.
Or real (= float4) if additional precision is not needed. 4 bytes each.
Or even numeric if you need absolute precision. 2 bytes for eac...
Regex exactly n OR m times
...character before) as you can see here: https://regex101.com/r/oC5oJ4/1
Finally, to match the one character distant match, you can add a positive look ahead (?=) on the "no 'x' after" or a positive look behind (?<=) on the "no 'x' before", like this: https://regex101.com/r/mC4uX3/1
(?<=[^x]|^...
How to commit no change and new message?
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There's rarely a good reason to do this, but the parameter is --allow-empty for empty commits (no files changed), in contrast to --allow-empty-message for empty commit messages. You can also read more by typing git help commit or visiting the online documentation.
While the tree object (w...
How to count the number of set bits in a 32-bit integer?
...Hamming Weight', 'popcount' or 'sideways addition'.
The 'best' algorithm really depends on which CPU you are on and what your usage pattern is.
Some CPUs have a single built-in instruction to do it and others have parallel instructions which act on bit vectors. The parallel instructions (like x86's ...
C++ Exceptions questions on rethrow of original exception
...he catch cause the rethrown exception to see the effect of append() being called?
4 Answers
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Chrome Extension Message passing: response not sent
...will keep the message channel open to the other end until sendResponse is called).
So you just need to add return true; after the call to getUrls to indicate that you'll call the response function asynchronously.
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