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Altering a column: null to not null
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This doesn't answer the problem. The default is already set, it's the NOT NULL which needs to be changed. With only your answer, all existing records will stay NULL and the problem remains.
– PandaWood
Aug 26 '15 at 0:16
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Can you grab or delete between parentheses in vi/vim?
... for "extended % matching" that you can find on the Vim homepage.
You can read the documentation on % and related motion commands by entering :help various-motions in command mode.
object-select
There is another set of motion commands that you can use in Visual mode to select various text objects...
Make xargs handle filenames that contain spaces
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The xargs utility reads space, tab, newline and end-of-file delimited strings from the standard input and executes utility with the strings as arguments.
You want to avoid using space as a delimiter. This can be done by changing the delimiter...
Pass a local file in to URL in Java
...ly omitted), followed by "/" and the path "foo/bar" (generally meant to be read as an absolute path). Thus "file:///foo/var". An URI that looks like "file:/foo/bar" is incorrect. See also: file URI scheme
– David Tonhofer
Sep 2 '15 at 14:00
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Java - How to create new Entry (key, value)
...e.
You said:
I can't use Map.Entry itself because apparently it's a read-only object that I can't instantiate new instanceof
That's not entirely accurate. The reason why you can't instantiate it directly (i.e. with new) is because it's an interface Map.Entry.
Caveat and tip
As noted in ...
How can I sort arrays and data in PHP?
...er in whether they keep key-value associations and sort by values or keys. Read their documentation for details.
Example usage:
usort($array, 'cmp');
usort will take two items from the array and call your cmp function with them. So cmp() will be called with $a as array('foo' => 'bar', 'baz' =>...
Histogram using gnuplot?
...to create a histogram (just use "with boxes") in gnuplot if my .dat file already has properly binned data. Is there a way to take a list of numbers and have gnuplot provide a histogram based on ranges and bin sizes the user provides?
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浅谈TCP优化 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...过如下方法来调整「cwnd」初始值：
shell> ip route | while read p; do
ip route change $p initcwnd 10;
done
需要提醒的是片面的提升发送端「cwnd」的大小并不一定有效，这是因为前面我们说过网络中实际传输的未经确认的数据...
Cleaning up the iPhone simulator
...ght change my schema, but the new database won't get copied, because one already exists.
15 Answers
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What is the purpose of “&&” in a shell command?
...understand what the program considers a "failure" and how it handles it by reading the documentation and, if necessary, the source code.
Your shell considers a return value of 0 for true, other positive numbers for false
Programs return a signal on exiting. They should return 0 if they exit succes...