大约有 40,000 项符合查询结果（耗时：0.0676秒） [XML]
Fastest check if row exists in PostgreSQL
...f a single row from the batch exists in the table because then I know they all were inserted.
8 Answers
...
Why are my JavaScript function names clashing?
...t. While incorrect in terms of parsing order, the code you have is semantically the same as the following since function declarations are hoisted:
function f() {
console.log("Me duplicate.");
}
var f = function() {
console.log("Me original.");
}
f();
Which in turn, with the exception of...
How to pass parameters to a view
....options:
initialize: function(options) {
this.options = options;
_.bindAll(this, 'render');
},
or use some finer ways as described by @Brave Dave.
share
|
improve this answer
|
...
How to remove the first character of string in PHP?
...
Note that lrtim will remove all :::::. Sometimes this is not desired behavior.
– CoR
Nov 20 '13 at 14:02
5
...
How to display full (non-truncated) dataframe information in html when converting from pandas datafr
...
Set the display.max_colwidth option to -1:
pd.set_option('display.max_colwidth', -1)
set_option docs
For example, in iPython, we see that the information is truncated to 50 characters. Anything in excess is ellipsized:
If you set the display...
invalid command code ., despite escaping periods, using sed
...of sed, the -i option expects an extension argument so your command is actually parsed as the extension argument and the file path is interpreted as the command code.
Try adding the -e argument explicitly and giving '' as argument to -i:
find ./ -type f -exec sed -i '' -e "s/192.168.20.1/new.domai...
git undo all uncommitted or unsaved changes
I'm trying to undo all changes since my last commit. I tried git reset --hard and git reset --hard HEAD after viewing this post . I responds with head is now at 18c3773... but when I look at my local source all the files are still there. What am I missing?
...
how to get android screen size programmatically, once and for all?
How can I find out my screen size programmatically,
in the units used by touch events
and View measurement/layout?
In other words, I want the coordinates
of the bottom-right corner of the screen,
in the coordinate system used by touch events'
getRawX()/getRawY() and View.getLocationOnScreen() .
...
How can you sort an array without mutating the original array?
...
this is really great.i think easier to understand than the concat and other approaches
– sktguha
Aug 31 at 20:02
...
Pandas dataframe get first row of each group
...If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6 first
6 7 fourth
To get n first records, you can use head():
>>> df.groupby('id').head(2).reset_index(drop=True)
...