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MySQL Cannot drop index needed in a foreign key constraint
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You have to drop the foreign key. Foreign keys in MySQL automatically create an index on the table (There was a SO Question on the topic).
ALTER TABLE mytable DROP FOREIGN KEY mytable_ibfk_1 ;
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Why would finding a type's initializer throw a NullReferenceException?
....cs:
(196c.1874): Access violation - code c0000005 (first chance)
mscorlib_ni!System.RuntimeType.GetConstructorImpl(System.Reflection.BindingFlags, System.Reflection.Binder, System.Reflection.CallingConventions, System.Type[], System.Reflection.ParameterModifier[])+0xa3:
000007fe`e5735403 488b4608 ...
JavaScript - Get Portion of URL Path
... URL:
It turns out that this schema is being standardized as an interface called URLUtils, and guess what? Both the existing window.location object and anchor elements implement the interface.
So you can use the same properties above for any URL — just create an anchor with the URL and access the...
Convert unix time to readable date in pandas dataframe
...12.15
3 1349979305 12.19
4 1350065705 12.15
In [25]: df['date'] = pd.to_datetime(df['date'],unit='s')
In [26]: df.head()
Out[26]:
date price
0 2012-10-08 18:15:05 12.08
1 2012-10-09 18:15:05 12.35
2 2012-10-10 18:15:05 12.15
3 2012-10-11 18:15:05 12.19
4 2012-10-12 18:15:...
How can I remove a character from a string using Javascript?
I am so close to getting this, but it just isn't right.
All I would like to do is remove the character r from a string.
The problem is, there is more than one instance of r in the string.
However, it is always the character at index 4 (so the 5th character).
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In JavaScript, why is “0” equal to false, but when tested by 'if' it is not false by itself?
...e special [[Get]] internal method defined below.
b. Return the result of calling the get internal method using base as its this value, and passing
GetReferencedName(V) for the argument
Or in other words, a string has a primitive base, which calls back the internal get method and ends up looking ...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...the pointer to void * as in printf("%p", (void *)str); When printing a size_t with printf, you should use "%zu" if using the latest C standard (C99).
– Chris Young
Oct 3 '08 at 7:44
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How do I specify new lines on Python, when writing on files?
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It depends on how correct you want to be. \n will usually do the job. If you really want to get it right, you look up the newline character in the os package. (It's actually called linesep.)
Note: when writing to files using the Python API, do not use the os.linesep. Just use ...
startActivityForResult() from a Fragment and finishing child Activity, doesn't call onActivityResult
FirstActivity.Java has a FragmentA.Java which calls startActivityForResult() .
SecondActivity.Java call finish() but onActivityResult never get called which is
written in FragmentA.Java .
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WPF OpenFileDialog with the MVVM pattern? [duplicate]
...ou would consume it.
public MyViewModel : ViewModel
{
private string _selectedPath;
public string SelectedPath
{
get { return _selectedPath; }
set { _selectedPath = value; OnPropertyChanged("SelectedPath"); }
}
private RelayCommand _openCommand;
pu...