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How to copy a row and insert in same table with a autoincrement field in MySQL?
....)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSERT column list and your SELECT:
insert into your_table (id, c1, c2, ...)
select 2, c1, c2, ...
from your_table
where i...
Simplest/Cleanest way to implement singleton in JavaScript?
...
return { // public interface
publicMethod1: function () {
// all private members are accessible here
},
publicMethod2: function () {
}
};
})();
This has been called the module pattern, it basically allows you to encapsulate private members on an object, by taking advant...
How to install Java SDK on CentOS?
I have CentOS 5, but I don't know the steps to install Java SDK on Linux.
12 Answers
...
How to write a scalable Tcp/Ip based server
...he best bet, using the Asynchronous sockets. This meant that clients not really doing anything actually required relatively little resources. Anything that does occur is handled by the .net thread pool.
I wrote it as a class that manages all connections for the servers.
I simply used a list to ho...
Why is parenthesis in print voluntary in Python 2.7?
...
In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
How to document class attributes in Python? [closed]
...y has a specific meaning in python. What you're talking about is what we call class attributes. Since they are always acted upon through their class, I find that it makes sense to document them within the class' doc string. Something like this:
class Albatross(object):
"""A bird with a fligh...
Recommended way of making React component/div draggable
...React.createClass({
getDefaultProps: function () {
return {
// allow the initial position to be passed in as a prop
initialPos: {x: 0, y: 0}
}
},
getInitialState: function () {
return {
pos: this.props.initialPos,
dragging: false,
rel: null // position...
MemoryCache does not obey memory limits in configuration
...ximum cache size, but in my tests it does not appear that the cache is actually obeying the limits.
7 Answers
...
Why is my git repository so big?
...he whole directory structure.
Edit: Here's Ian's one liner for recreating all branches in the new repo:
d1=#original repo
d2=#new repo (must already exist)
cd $d1
for b in $(git branch | cut -c 3-)
do
git checkout $b
x=$(git rev-parse HEAD)
cd $d2
git checkout -b $b $x
cd $d1
d...
What is the difference between '/' and '//' when used for division?
...floating point division, and the latter is floor division, sometimes also called integer division.
In Python 2.2 or later in the 2.x line, there is no difference for integers unless you perform a from __future__ import division, which causes Python 2.x to adopt the 3.x behavior.
Regardless of the ...