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Difference between a Factory, Provider and a Service?
What is the difference between the terms Factory, Provider and Service?
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How do I center align horizontal menu?
... involves a widthless float wrapper that is floated to the left and then shifted off screen to the left width position:relative; left:-50%. Next the nested inner element is reversed and a relative position of +50% is applied. This has the effect of placing the element dead in the center. Relative po...
Can I find out the return value before returning while debugging in Visual Studio?
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Not that I know of. Note that if you do add a variable, it will get removed by the compiler in release builds anyway...
Update:
This functionality has been added to VS2013.
You can see the return values in the autos windows or use $ReturnValue in the wat...
how do you filter pandas dataframes by multiple columns
To filter a dataframe (df) by a single column, if we consider data with male and females we might:
6 Answers
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Importance of varchar length in MySQL table
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No, in the sense that if the values you're storing in that column are always (say) less than 50 characters, declaring the column as varchar(50) or varchar(200) has the same performance.
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Format a date using the new date time API
...ds of temporal objects.
JSR-310 has choosen another way, namely to allow different temporal types which consist of type-specific sets of supported built-in fields. The natural consequence is that not every possible field is supported by every type (and users can even define their own specialized fi...
How to move columns in a MySQL table?
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If empName is a VARCHAR(50) column:
ALTER TABLE Employees MODIFY COLUMN empName VARCHAR(50) AFTER department;
EDIT
Per the comments, you can also do this:
ALTER TABLE Employees CHANGE COLUMN empName empName VARCHAR(50) A...
Reading a binary file with python
I find particularly difficult reading binary file with Python. Can you give me a hand?
I need to read this file, which in Fortran 90 is easily read by
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Scrollview vertical and horizontal in android
...sureSpec.makeMeasureSpec(lp.leftMargin + lp.rightMargin, MeasureSpec.UNSPECIFIED);
Edit: The Link doesn't work anymore but here is a link to an old version of the blogpost.
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Filtering for empty or NULL names in a queryset
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You could do this:
Name.objects.exclude(alias__isnull=True)
If you need to exclude null values and empty strings, the preferred way to do so is to chain together the conditions like so:
Name.objects.exclude(alias__isnull=True).exclude(alias__exact='')
Chaining these methods togethe...