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How to create a unique index on a NULL column?
...rver 2005. I want to constrain the values in a column to be unique, while allowing NULLS.
4 Answers
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E731 do not assign a lambda expression, use a def
...rst form means that the name of the resulting
function object is specifically 'f' instead of the generic '<lambda>'.
This is more useful for tracebacks and string representations in
general. The use of the assignment statement eliminates the sole
benefit a lambda expression can offer o...
Prevent the keyboard from displaying on activity start
...g both in code, and in xml! Indeed, this is the most correct answer! Especially since it was probably that 3 minutes you spent writing both methods that made you not first ;-)
– eric
Apr 21 '17 at 1:13
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Enable remote MySQL connection: ERROR 1045 (28000): Access denied for user
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You have to put this as root:
GRANT ALL PRIVILEGES ON *.* TO 'USERNAME'@'IP' IDENTIFIED BY 'PASSWORD' with grant option;
;
where IP is the IP you want to allow access, USERNAME is the user you use to connect, and PASSWORD is the relevant password.
If you wa...
How to securely store access token and secret in Android?
...other apps cannot access them. On a rooted devices, if the user explicitly allows access to some app that is trying to read them, the app might be able to use them, but you cannot protect against that. As for encryption, you have to either require the user to enter the decrypt passphrase every time ...
HEAD and ORIG_HEAD in Git
..., and it is a commit on top of which "git commit" would make a new one. Usually HEAD is symbolic reference to some other named branch; this branch is currently checked out branch, or current branch. HEAD can also point directly to a commit; this state is called "detached HEAD", and can be understood...
Overriding a JavaScript function while referencing the original
...tioned in the comments, be sure to include the () at the end. You want to call the outer function and store the result (one of the two inner functions) in a, not store the outer function itself in a.
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Where and why do I have to put the “template” and “typename” keywords?
...iler doesn't need to know the meaning of a name in order to parse and basically know what action a line of code does. In C++, the above however can yield vastly different interpretations depending on what t means. If it's a type, then it will be a declaration of a pointer f. However if it's not a ty...
One line if statement not working
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@JayKilleen You're correct. Ruby is all about clever tricks, but it's that clever (:
– Nikita Rybak
Jan 23 '15 at 7:47
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Append a NumPy array to a NumPy array
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Well, the error message says it all: NumPy arrays do not have an append() method. There's a free function numpy.append() however:
numpy.append(M, a)
This will create a new array instead of mutating M in place. Note that using numpy.append() involves c...