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Possibility of duplicate Mongo ObjectId's being generated in two different collections?
... "abc" }
> db.foo.insert({_id: 'abc', data:'xyz'})
E11000 duplicate key error index: test.foo.$_id_ dup key: { : "abc" }
So, absolutely don't rely on _id's being unique across collections, and since you don't control the ObjectId generation function, don't rely on it.
It's possible to create...
Command to list all files in a folder as well as sub-folders in windows
I tried searching for a command that could list all the file in a directory as well as subfolders using a command prompt command.
I have read the help for "dir" command but coudn't find what I was looking for.
Please help me what command could get this.
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Importing variables from another file?
...t, but it seems like python can't find the file1, because I'm getting this error: ImportError: No module named file1
– Hilder Vitor Lima Pereira
May 29 '15 at 23:52
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Detect Windows version in .net
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What about the getOSArchitecture() method? Error: "The name 'getOSArchitecture' does not exist in the current context."
– Lonnie Best
May 21 '10 at 21:08
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How to print a debug log?
...', print_r($foo, TRUE)) will nicely dump the value of $foo into the Apache error log.
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How should strace be used?
...see what your OS does. It basically saves the trouble of writing logging / error-check code for one-off experiments. (Or if you're writing in asm or something where there's a good chance you accidentally passed the wrong args or even call number.) strace is much faster than GDB because it looks up...
How can I make pandas dataframe column headers all lowercase?
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df.columns = df.columns.str.lower()
is the easiest but will give an error if some headers are numeric
if you have numeric headers then use this:
df.columns = [str(x).lower() for x in df.columns]
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Django Forms: if not valid, show form with error message
...e view when the form is not valid then in template you can access the form errors using form.errors.
{% if form.errors %}
{% for field in form %}
{% for error in field.errors %}
<div class="alert alert-danger">
<strong>{{ error|escape }}</stron...
str performance in python
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105
'%s' % 100000 is evaluated by the compiler and is equivalent to a constant at run-time.
>&g...
Static method in a generic class?
... I tried Clazz<Object>.doIt(object) and got a compile-time error! "Syntax error on token(s), misplaced construct(s)". Clazz.doIt(object) works fine though, not even a warning.
– André Chalella
Jun 1 '09 at 20:14
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