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Best practices for in-app database migration for Sqlite
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I maintain an application that periodically needs to update a sqlite database and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing w...
C#: Assign same value to multiple variables in single statement
...nteresting to know that the get accessor of the intermediate value is not called. Only the set accessor is invoked for all property accessed in the assignation sequence.
Take for example a class that write to the console everytime the get and set accessor are invoked.
static void Main(string[] arg...
How do you install Boost on MacOS?
How do you install Boost on MacOS?
Right now I can't find bjam for the Mac.
10 Answers
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How to make the 'cut' command treat same sequental delimiters as one?
... characters to tab. For example: I came here looking for a way to automatically export my display: who am i | tr -s ' ()' '\t' | cut -f5
– Leo
Mar 28 '16 at 23:24
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Is it better to use std::memcpy() or std::copy() in terms to performance?
...y.
I wrote a C++ SHA-2 implementation. In my test, I hash 5 strings using all four SHA-2 versions (224, 256, 384, 512), and I loop 300 times. I measure times using Boost.timer. That 300 loop counter is enough to completely stabilize my results. I ran the test 5 times each, alternating between the m...
Simple example of threading in C++
...ill execute, followed by the function's parameters. The thread is automatically started upon construction.
If later on you want to wait for the thread to be done executing the function, call:
t1.join();
(Joining means that the thread who invoked the new thread will wait for the new thread to fi...
Convert hex string to int in Python
... 16)
With the 0x prefix, Python can distinguish hex and decimal automatically.
>>> print int("0xdeadbeef", 0)
3735928559
>>> print int("10", 0)
10
(You must specify 0 as the base in order to invoke this prefix-guessing behavior; omitting the second parameter means to assume ba...
How can I access “static” class variables within class methods in Python?
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As with all good examples, you've simplified what you're actually trying to do. This is good, but it is worth noting that python has a lot of flexibility when it comes to class versus instance variables. The same can be said of meth...
What is the difference between partitioning and bucketing a table in Hive ?
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Partitioning data is often used for distributing load horizontally, this has performance benefit, and helps in organizing data in a logical fashion. Example: if we are dealing with a large employee table and often run queries with WHERE clauses that restrict the results to a particular ...
Are tuples more efficient than lists in Python?
...l be more like the tuple example above than the list example, but do you really believe that means performance will be similar?
– mzz
Jan 31 '10 at 15:21
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