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Spring Boot application as a Service
...
For a proper boot sequence you might want to add ordering statements to the [Unit] section, e.g. After=mysql.service, Before=apache2.service.
– rustyx
Jan 25 at 9:41
...
What are “first class” objects?
...ally has a fairly rich and sophisticated interface.
>>> dir(2)
['__abs__', '__add__', '__and__', '__class__', '__cmp__', '__coerce__', '__delattr__', '__div__', '__divmod__', '__doc__', '__float__', '__floordiv__', '__getattribute__', '__getnewargs__', '__hash__', '__hex__', '__index__', '...
Build a Basic Python Iterator
... to the iterator protocol, which basically means they provide two methods: __iter__() and __next__().
The __iter__ returns the iterator object and is implicitly called
at the start of loops.
The __next__() method returns the next value and is implicitly called at each loop increment. This met...
Python dictionary from an object's fields
...s'. To build a dictionary from an arbitrary object, it's sufficient to use __dict__. Usually, you'll declare your methods at class level and your attributes at instance level, so __dict__ should be fine. For example:
>>> class A(object):
... def __init__(self):
... self.b = 1
... ...
Difference between local and global indexes in DynamoDB
... make sure you pay special attention to the following requirements:
In order for a table write to succeed, the provisioned throughput
settings for the table and all of its global secondary indexes must
have enough write capacity to accommodate the write; otherwise, the
write to the table w...
Multi-line string with extra space (preserved indentation)
...o use a helper function and some variable substitution tricks:
unset text
_() { text="${text}${text+
}${*}"; }
# That's an empty line which demonstrates the reasoning behind
# the usage of "+" instead of ":+" in the variable substitution
# above.
_ ""
_ "this is line one"
_ "this is line two"
_ "...
How do I correctly clean up a Python object?
__del__(self) above fails with an AttributeError exception. I understand Python doesn't guarantee the existence of "global variables" (member data in this context?) when __del__() is invoked. If that is the case and this is the reason for the exception, how do I make sure the object destructs...
Ruby: Can I write multi-line string with no concatenation?
...
p <<END_SQL.gsub(/\s+/, " ").strip
SELECT * FROM users
ORDER BY users.id DESC
END_SQL
# >> "SELECT * FROM users ORDER BY users.id DESC"
The latter would mostly be for situations that required more flexibility in the processing. I personally don't like it, it puts the proc...
What is a “Bitmap heap scan” in a query plan?
... is different from an index scan, where the index is visited row by row in order -- meaning a disk page may get visited multiple times.
Re: the question in your comment... Yep, that's exactly it.
An index scan will go through rows one by one, opening disk pages again and again, as many times as ...
How do I check OS with a preprocessor directive?
...ecks. Here are a few of them, with links to where they're found:
Windows
_WIN32 Both 32 bit and 64 bit
_WIN64 64 bit only
Unix (Linux, *BSD, Mac OS X)
See this related question on some of the pitfalls of using this check.
unix
__unix
__unix__
Mac OS X
__APPLE__
__MACH__
Both are de...