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How can I select rows with most recent timestamp for each key value?
I have a table of sensor data. Each row has a sensor id, a timestamp, and other fields. I want to select a single row with latest timestamp for each sensor, including some of the other fields.
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How to perform runtime type checking in Dart?
...tp://www.dartlang.org/articles/optional-types/.
Here's an example:
class Foo { }
main() {
var foo = new Foo();
if (foo is Foo) {
print("it's a foo!");
}
}
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“Variable” variables in Javascript?
... your problem.
If you have a fixed set of names, such as
// BAD
var foo = 42;
var bar = 21;
var key = 'foo';
console.log(eval(key));
store the those name/values as properties of an object and use bracket notation to look them up dynamically:
// GOOD
var obj = {
foo: 42,
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How to mock an import
...e submodules, but you'll want to mock each module. Say you have this:
from foo import This, That, andTheOtherThing
from foo.bar import Yada, YadaYada
from foo.baz import Blah, getBlah, boink
To mock, simply do the below before the module that contains the above is imported:
sys.modules['foo'] = Mag...
How to avoid “too many parameters” problem in API design?
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Iterate over the lines of a string
...
Here are three possibilities:
foo = """
this is
a multi-line string.
"""
def f1(foo=foo): return iter(foo.splitlines())
def f2(foo=foo):
retval = ''
for char in foo:
retval += char if not char == '\n' else ''
if char == '\n':
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What does if __name__ == “__main__”: do?
...e how imports and scripts work. Suppose the following is in a file called foo.py.
# Suppose this is foo.py.
print("before import")
import math
print("before functionA")
def functionA():
print("Function A")
print("before functionB")
def functionB():
print("Function B {}".format(math.sqrt(...
How can I ignore everything under a folder in Mercurial
...sitory is in E:\Dev for example, hg status will apply the patterns against foo/bar/file1.c and such. Anchors apply to this path.
So:
Glob applies to path elements and is rooted to element parts
foo matches any folder (or file) named foo (not to "foobar" nor "barfoo")
*foo* matches any folder or f...
Select random row from a sqlite table
... How to extend this solution to a join? When using SELECT a.foo FROM a JOIN b ON a.id = b.id WHERE b.bar = 2 ORDER BY RANDOM() LIMIT 1; I always get the same row.
– Helmut Grohne
Sep 19 '13 at 8:18
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clear javascript console in Google Chrome
I was wondering if I could clear up the console with some command..
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