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Django-DB-Migrations: cannot ALTER TABLE because it has pending trigger events
...is you can either use a data migration or manually (manage.py shell) go in and update non-compliant values
– mgojohn
Oct 26 '14 at 23:13
...
Remove leading comma from a string
...tring(1)
However, if you want to be able to detect if the comma is there and remove it if it is, then something like:
if (str[0] == ',') {
str = str.substring(1);
}
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Pandas read_csv low_memory and dtype options
...emory warning is because guessing dtypes for each column is very memory demanding. Pandas tries to determine what dtype to set by analyzing the data in each column.
Dtype Guessing (very bad)
Pandas can only determine what dtype a column should have once the whole file is read. This means nothing can...
Why JSF saves the state of UI components on server?
...the state of UI components on the server side ?
Because HTTP is stateless and JSF is stateful. The JSF component tree is subject to dynamic (programmatic) changes. JSF simply needs to know the exact state as it was when the form had been displayed to the enduser, so that it can successfully process...
Which exception should I raise on bad/illegal argument combinations in Python?
...tion..
def import_to_orm(name, save=False, recurse=False):
if recurse and not save:
raise ValueError("save must be True if recurse is True")
There's really no point in doing class BadValueError(ValueError):pass - your custom class is identical in use to ValueError, so why not use that...
Date format Mapping to JSON Jackson
... want this to then instantiate a BasicDbObject (MongoDB API) from the Map, and consequently store the variable in a MongoDB DB collection as Date (not as Long or String). Is this even possible? Thank you
– RedEagle
Aug 4 '16 at 22:36
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What is the best way to repeatedly execute a function every x seconds?
...er (just like an NSTimer in Objective C). This code will run as a daemon and is effectively like calling the python script every minute using a cron, but without requiring that to be set up by the user.
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What is Vim recording and how can it be disabled?
...
You start recording by q<letter>
and you can end it by typing q again.
Recording is a really useful feature of Vim.
It records everything you type. You can then replay it simply by typing @<letter>.
Record search, movement, replacement...
One of the...
How to fix 'sudo: no tty present and no askpass program specified' error?
...ile some sources using a makefile. In the makefile there is a bunch of commands that need to be ran as sudo .
26 Answers
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What is the difference between a field and a property?
In C#, what makes a field different from a property, and when should a field be used instead of a property?
32 Answers
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