大约有 48,000 项符合查询结果（耗时：0.0258秒） [XML]
How to get distinct values from an array of objects in JavaScript?
...u are using ES6/ES2015 or later you can do it this way:
const data = [
{ group: 'A', name: 'SD' },
{ group: 'B', name: 'FI' },
{ group: 'A', name: 'MM' },
{ group: 'B', name: 'CO'}
];
const unique = [...new Set(data.map(item => item.group))]; // [ 'A', 'B']
Here is an example on how to...
Bigger Glyphicons
...
great! In my case, I had an input-group-btn with a button, and this button was a little bigger. So I just gave "font-size:95%" for my glyphicon and it was solved.
– victorf
Jan 22 '16 at 17:26
...
How to cherry-pick multiple commits
...
You can use a serial combination of git rebase and git branch to apply a group of commits onto another branch. As already posted by wolfc the first command actually copies the commits. However, the change is not visible until you add a branch name to the top most commit of the group.
Please open ...
Select row with most recent date per user
...
No need to trying reinvent the wheel, as this is common greatest-n-per-group problem. Very nice solution is presented.
I prefer the most simplistic solution (see SQLFiddle, updated Justin's) without subqueries (thus easy to use in views):
SELECT t1.*
FROM lms_attendance AS t1
LEFT OUTER JOIN l...
What good are SQL Server schemas?
...
Schemas logically group tables, procedures, views together. All employee-related objects in the employee schema, etc.
You can also give permissions to just one schema, so that users can only see the schema they have access to and nothing else...
mongodb count num of distinct values per field/key
...
Here is example of using aggregation API. To complicate the case we're grouping by case-insensitive words from array property of the document.
db.articles.aggregate([
{
$match: {
keywords: { $not: {$size: 0} }
}
},
{ $unwind: "$keywords" },
{
...
How to determine if a number is a prime with regex?
...(..+?)\\1+
The second part of the regex is a little trickier, relying on groups and backreferences. A group is anything in parentheses, which will then be captured and stored by the regex engine for later use. A backreference is a matched group that is used later on in the same regex.
The group c...
JPG vs. JPEG image formats
...r an image format proposed and supported by the Joint Photographic Experts Group. The two terms have the same meaning and are interchangeable.
To read on, check out Difference between JPG and JPEG.
The reason for the different file extensions dates back to the early versions of Windows. The or...
Find string between two substrings [duplicate]
...iwantthis123jasd'
result = re.search('asdf=5;(.*)123jasd', s)
print(result.group(1))
share
|
improve this answer
|
follow
|
...
Which is the correct shorthand - “regex” or “regexp” [closed]
...encer referred to his famous library as "regexp" as early as 1986. (http://groups.google.com/group/mod.sources/msg/ab37bf1ead7209ec?)
The Jargon File listed "regexp (also regex, reg-ex)" as early as 1991. (http://groups.google.com/group/misc.misc/msg/e75ca9cb78220ea0?)
JavaScript and Ruby both have ...