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Does SQLAlchemy have an equivalent of Django's get_or_create?
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That's basically the way to do it, there is no shortcut readily available AFAIK.
You could generalize it ofcourse:
def get_or_create(session, model, defaults=None, **kwargs):
instance = session.query(model).filter_by(**kwargs).firs...
Stashing only un-staged changes in Git
... answered Oct 4 '11 at 16:10
vhallacvhallac
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Javascript - Append HTML to container element without innerHTML
...;
font-size: 30px;
outline: none;
padding: 0 20px;
transition: all .3s;
}
button:hover {
background: rgba(7, 99, 53, 1);
color: rgba(255,255,255,1);
}
p {
font-size: 20px;
font-weight: bold;
}
<button type="button" onclick="addChild()">Append Child</button>
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How to autosize a textarea using Prototype?
...nal sales application for the company I work for, and I've got a form that allows the user to change the delivery address.
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Make install, but not to default directories?
I want to run 'make install' so I have everything I need, but I'd like it to install the things in their own folder as opposed to the system's /usr/bin etc. is that possible? even if it references tools in the /usr/bin etc.?
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pandas dataframe columns scaling with sklearn
...and I'd like to apply sklearn's min_max_scaler to some of the columns. Ideally, I'd like to do these transformations in place, but haven't figured out a way to do that yet. I've written the following code that works:
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Where to store global constants in an iOS application?
...sets of constants to include before #include-ing the constants file (stops all those "defined but not used" compiler warnings).
– user244343
Aug 19 '11 at 2:26
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Python: Why is functools.partial necessary?
...rticular) appear to like lambda just fine – I say "most", definitely not all, because Guido and I assuredly are among those "familiar with" (etc) yet think of lambda as an eyesore anomaly in Python...
He was repentant of ever having accepted it into Python whereas planned to remove it from Python ...
How do you manage databases in development, test, and production?
...of good options. I wouldn't use the "restore a backup" strategy.
Script all your schema changes, and have your CI server run those scripts on the database. Have a version table to keep track of the current database version, and only execute the scripts if they are for a newer version.
Use a migr...
Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...rst time you iterate over it. For example, this will print the headline of all entries in the database:
for e in Entry.objects.all():
print e.headline
So your ten million rows are retrieved, all at once, when you first enter that loop and get the iterating form of the queryset. The wait ...