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Insert, on duplicate update in PostgreSQL?
...mple 38-2. Exceptions with UPDATE/INSERT
This example uses exception handling to perform either UPDATE or INSERT, as appropriate:
CREATE TABLE db (a INT PRIMARY KEY, b TEXT);
CREATE FUNCTION merge_db(key INT, data TEXT) RETURNS VOID AS
$$
BEGIN
LOOP
-- first try to update the key...
Python group by
...ultdict(list)
>>> for v, k in input: res[k].append(v)
...
Then, convert that dictionary into the expected format.
>>> [{'type':k, 'items':v} for k,v in res.items()]
[{'items': ['9085267', '11788544'], 'type': 'NOT'}, {'items': ['5238761', '5349618', '962142', '7795297', '7341464...
What is the relationship between Looper, Handler and MessageQueue in Android?
I have checked the official Android documentation/guide for Looper , Handler and MessageQueue . But I couldn't get it. I am new to android, and got very confused with these concepts.
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Is there a typical state machine implementation pattern?
We need to implement a simple state machine in C .
Is a standard switch statement the best way to go?
We have a current state (state) and a trigger for the transition.
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while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...hat the compiler would generate the same byte code for while(True): pass and while(1): pass , but this is actually not the case in python2.7.
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Request is not available in this context
I'm running IIS 7 Integrated mode and I'm getting
11 Answers
11
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Reuse Cucumber steps
...thing", "fill something". The natural way would be reuse steps, instead of convert each step into a call to a function. IMO, calling steps inside steps should just be improved.
– dgmora
Jun 27 '13 at 16:28
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Does a const reference class member prolong the life of a temporary?
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Only local const references prolong the lifespan.
The standard specifies such behavior in §8.5.3/5, [dcl.init.ref], the section on initializers of reference declarations. The reference in your example is bound to the constructor's argument n, and becomes invalid when the object n...
How do I combine a background-image and CSS3 gradient on the same element?
...ut images that aren't already semi-transparent can't be easily/dynamically converted to be used in this manner. That's why I find the approach of putting the gradient first more generally useful.
– waldyrious
Jan 14 '18 at 13:23
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What are the differences between Rust's `String` and `str`?
...an be seen as a fixed-length String that cannot be resized (you can always convert it into a String if you want to resize it).
A very similar relationship exists between [T] and Vec<T> except there is no UTF-8 constraint and it can hold any type whose size is not dynamic.
The use of str on t...