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Update multiple rows in same query using PostgreSQL
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This is wrong... You will update all rows, even if it is not '123' nor '345'. You should use WHERE column_b IN ('123','456')...
– MatheusOl
Sep 14 '13 at 3:54
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Double Iteration in List Comprehension
...f_words
I like to think of list comprehension as stretching code horizontally.
Try breaking it up into:
# List Comprehension
[word for sentence in text for word in sentence]
Example:
>>> text = (("Hi", "Steve!"), ("What's", "up?"))
>>> [word for sentence in text for word in...
mongodb: insert if not exists
... has built-in support for this. Pass an extra parameter to your update() call: {upsert:true}. For example:
key = {'key':'value'}
data = {'key2':'value2', 'key3':'value3'};
coll.update(key, data, upsert=True); #In python upsert must be passed as a keyword argument
This replaces your if-find-els...
How to print a percentage value in python?
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Is float(1) really more pythonic than 1.?
– Tobias Kienzler
Jul 17 '13 at 7:58
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Why can't decimal numbers be represented exactly in binary?
...(and will do so if you try to divide 1 by that number).
Although 0.1 is usually used as the simplest example of an exact decimal number which can't be represented exactly in binary floating point, arguably 0.2 is a simpler example as it's 1/5 - and 5 is the prime that causes problems between decimal...
How do I PHP-unserialize a jQuery-serialized form?
.... You do indeed need to parse the string that serialize returns. See the really popular answer below.
– Isaac Lubow
Mar 1 '19 at 2:17
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What is content-type and datatype in an AJAX request?
... That's what I like about SO...get rep for stating the obvious... >_<
– Christoph
Sep 9 '13 at 15:40
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receiver type *** for instance message is a forward declaration
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That basically means that you need to import the .h file containing the declaration of States.
However, there is a lot of other stuff wrong with your code.
You're -init'ing an object without +alloc'ing it. That won't work
You're dec...
Swift Programming: getter/setter in stored property
...the new value that you assign will replace the one that was just set.
So all you have to do is this:
var rank: Int = 0 {
didSet {
// Say 1000 is not good for you and 999 is the maximum you want to be stored there
if rank >= 1000 {
rank = 999
}
}
}
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Case objects vs Enumerations in Scala
... deal with an Option[Currency] type that would clearly indicate there is really a matching problem and "encourage" the user of the API to sort it out him/herself.
To follow up on the other answers here, the main drawbacks of case objects over Enumerations are:
Can't iterate over all instances of t...