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Duplicating a MySQL table, indices, and data
...
This should have been the accepted answer. As this copies all the indexes including primary key and auto_increment
– Channaveer Hakari
Oct 11 '18 at 6:06
add ...
Python: Checking if a 'Dictionary' is empty doesn't seem to work
...; not dct
True
>>>
Thus, your isEmpty function is unnecessary. All you need to do is:
def onMessage(self, socket, message):
if not self.users:
socket.send("Nobody is online, please use REGISTER command" \
" in order to register into the server")
else:...
What's the recommended approach to resetting migration history using Django South?
...inted out by @thnee below. Since your
answer has so many upvotes I'd really appreciate it if you could edit
it and add at least a warning about this, or (even better) change it
to reflect @hobs approach (which is just as convenient, but doesn't
affect other apps) - thanks! – chris...
How can I delete all Git branches which have been merged?
...anches which have already been merged? Is there an easy way to delete them all instead of deleting them one by one?
45 Answ...
What is the relative performance difference of if/else versus switch statement in Java?
...ic interface Action {
void execute(String input);
}
And get hold of all implementations in some Map. You can do this either statically or dynamically:
Map<String, Action> actions = new HashMap<String, Action>();
Finally replace the if/else or switch by something like this (leav...
Interfaces — What's the point?
...ntract. A set of public methods any implementing class has to have. Technically, the interface only governs syntax, i.e. what methods are there, what arguments they get and what they return. Usually they encapsulate semantics as well, although that only by documentation.
You can then have differen...
How to hash some string with sha256 in Java?
...
SHA-256 isn't an "encoding" - it's a one-way hash.
You'd basically convert the string into bytes (e.g. using text.getBytes(StandardCharsets.UTF_8)) and then hash the bytes. Note that the result of the hash would also be arbitrary binary data, and if you want to represent that in a strin...
The difference between sys.stdout.write and print?
...ble, but by default with a space between args and newline at the end) and calls the write function of a given object. By default this object is sys.stdout, but you can pass a file using the "chevron" form. For example:
print >> open('file.txt', 'w'), 'Hello', 'World', 2+3
See: https://docs....
Batch file to delete files older than N days
I am looking for a way to delete all files older than 7 days in a batch file. I've searched around the web, and found some examples with hundreds of lines of code, and others that required installing extra command line utilities to accomplish the task.
...
What does “abstract over” mean?
...the similarities. We say that we abstract over the differences, but this really means we're integrating by the similarities.
For example, consider a program that takes the sum of the numbers 1, 2, and 3:
val sumOfOneTwoThree = 1 + 2 + 3
This program is not very interesting, since it's not very a...