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How do I delete unpushed git commits?
...or me, git reset --hard origin says fatal: ambiguous argument 'origin': unknown revision or path not in the working tree.. Why?
– trss
Jul 10 '13 at 12:01
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How to change a nullable column to not nullable in a Rails migration?
I created a date column in a previous migration and set it to be nullable. Now I want to change it to be not nullable. How do I go about doing this assuming there are null rows in that database? I'm ok with setting those columns to Time.now if they're currently null.
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Checking out Git tag leads to “detached HEAD state”
..., a commit, a date specifier, an ordinal specifier or many other things.
Now a branch is just like a tag but is movable. When you are "on" a branch and make a commit, the branch is moved to the new commit you made indicating it's current position.
Your HEAD is pointer to a branch which is consid...
How to remove an element from a list by index
...nswered Mar 9 '09 at 18:21
unbeknownunbeknown
54
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Why can a class not be defined as protected?
...
As you know default is for package level access and protected is for package level plus non-package classes but which extends this class (Point to be noted here is you can extend the class only if it is visible!).
Let's put it in th...
Basic example of using .ajax() with JSONP?
...lly a simply trick to overcome XMLHttpRequest same domain policy. (As you know one cannot send AJAX (XMLHttpRequest) request to a different domain.)
So - instead of using XMLHttpRequest we have to use script HTMLl tags, the ones you usually use to load JS files, in order for JS to get data from ano...
How to fix Error: “Could not find schema information for the attribute/element” by creating schema
...e- app.xsd which I saved to the root directory. The errors dissapeared but now i get a warning: "The global element 'configuration' has aleady been declared". Any idea on how to fix this?
– Brian McCarthy
Mar 15 '11 at 16:10
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PHP ORMs: Doctrine vs. Propel
...t more. The release is planned for the end of Q1 2010, but you can test it now in your Symfony projects.
– Jan Fabry
Jan 15 '10 at 7:24
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How to convert a data frame column to numeric type?
... that you should apply transform function in order to complete your task.
Now I'm about to demonstrate certain "conversion anomaly":
# create dummy data.frame
d <- data.frame(char = letters[1:5],
fake_char = as.character(1:5),
fac = factor(1:5),
...
“X does not name a type” error in C++
...is is okay, it's just a pointer;
// we can point to something without knowing how that something is defined
foo* fp;
// likewise, we can form a reference to it
void some_func(foo& fr);
// but this would be an error, as before, because it requires a definition
/* foo fo...