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Any reason not to use '+' to concatenate two strings?
...e Python interpreter has to create a new string object for each iteration, and it ends up taking quadratic time. (Recent versions of CPython can apparently optimize this in some cases, but other implementations can't, so programmers are discouraged from relying on this.) ''.join is the right way t...
Create request with POST, which response codes 200 or 201 and content
...he 201 (Created) status code indicates that the request has been fulfilled and has resulted in one or more new resources being created. The primary resource created by the request is identified by either a Location header field in the response or, if no Location field is received, by the effective ...
COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
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Bottom Line
Use either COUNT(field) or COUNT(*), and stick with it consistently, and if your database allows COUNT(tableHere) or COUNT(tableHere.*), use that.
In short, don't use COUNT(1) for anything. It's a one-trick pony, which rarely does what you want, and in those ...
How would Git handle a SHA-1 collision on a blob?
This probably never happened in the real-world yet, and may never happen, but let's consider this: say you have a git repository, make a commit, and get very very unlucky: one of the blobs ends up having the same SHA-1 as another that is already in your repository. Question is, how would Git handle ...
Passing arrays as parameters in bash
... --iread --msi --iwrite
Edit/notes: (from comments below)
descTable and optsTable are passed as names and are expanded in the function. Thus no $ is needed when given as parameters.
Note that this still works even with descTable etc being defined with local, because locals are visible to the ...
How to make a great R reproducible example
... teaching, sending a bug report or searching for guidance on mailing lists and here on Stack Overflow, a reproducible example is often asked and always helpful.
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What's the difference between deque and list STL containers?
...e is very much like a vector: like vector, it is a sequence that supports random access to elements, constant time insertion and removal of elements at the end of the sequence, and linear time insertion and removal of elements in the middle.
The main way in which deque differs from vector is that de...
Redirect STDERR / STDOUT of a process AFTER it's been started, using command line?
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Short of closing and reopening your tty (i.e. logging off and back on, which may also terminate some of your background processes in the process) you only have one choice left:
attach to the process in question using gdb, and run:
p dup2(...
How accurately should I store latitude and longitude?
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Actually, equator is best case. One latitude and one longitude degree are the same size at the equator (69 miles), but one degree of longitude shrinks to zero as it approaches either of the poles. Here's a very nice explanation: nationalatlas.gov/articles/mapping/a_latl...
Shards and replicas in Elasticsearch
I am trying to understand what shard and replica is in Elasticsearch, but I didn't manage to understand it. If I download Elasticsearch and run the script, then from what I know I have started a cluster with a single node. Now this node (my PC) have 5 shards (?) and some replicas (?).
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