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SQL update fields of one table from fields of another one
...ng the column names?
General solution with dynamic SQL
You don't need to know any column names except for some unique column(s) to join on (id in the example). Works reliably for any possible corner case I can think of.
This is specific to PostgreSQL. I am building dynamic code based on the the inf...
to_string is not a member of std, says g++ (mingw)
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This is a known bug under MinGW. Relevant Bugzilla. In the comments section you can get a patch to make it work with MinGW.
This issue has been fixed in MinGW-w64 distros higher than GCC 4.8.0 provided by the MinGW-w64 project. Despite...
How do I pass a unique_ptr argument to a constructor or a function?
I'm new to move semantics in C++11 and I don't know very well how to handle unique_ptr parameters in constructors or functions. Consider this class referencing itself:
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Reading binary file and looping over each byte
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# Do stuff with byte.
byte = f.read(1)
python 3.8
From now on thanks to := operator the above code can be written in a shorter way.
with open("myfile", "rb") as f:
while (byte := f.read(1)):
# Do stuff with byte.
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Why covariance and contravariance do not support value type
...hout any change in representation; the native code itself doesn't need to know what you're doing with the values at all, so long as the infrastructure has guaranteed that it will definitely be valid.
For value types, that doesn't work - to treat an IEnumerable<int> as an IEnumerable<object...
Loading cross-domain endpoint with AJAX
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I'm posting this in case someone faces the same problem I am facing right now. I've got a Zebra thermal printer, equipped with the ZebraNet print server, which offers a HTML-based user interface for editing multiple settings, seeing the printer's current status, etc. I need to get the status of the...
Why do we use arrays instead of other data structures?
...gramming languages had improved upon this and by that replaced them. I see now that they aren't replaced but rather given new life, so to speak.
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How to duplicate sys.stdout to a log file?
...'s either no solution, or I'm doing something so non-standard that nobody knows - I'll revise my question to also ask: What is the best way to accomplish logging when a python app is making a lot of system calls?
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How many socket connections can a web server handle?
...xy requests through to some backend service(s), in which case the "server" now becomes a "client" and may well have to worry about ephemeral port exhaustion (eg: nginx.com/blog/overcoming-ephemeral-port-exhaustion-nginx-plus). I'm sure you know that, but mentioning it for others (:
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HTML text input field with currency symbol
... bad so I'm using display:inline-block combined with vertical-align:bottom now :) I cannot quickly make a fiddle though, there's too much other CSS going in my current example ;-)
– kluka
Aug 1 '16 at 15:50
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