大约有 30,000 项符合查询结果（耗时：0.0449秒） [XML]
Add new field to every document in a MongoDB collection
...> db.foo.find()
> db.foo.insert({"test":"a"})
> db.foo.find()
{ "_id" : ObjectId("4e93037bbf6f1dd3a0a9541a"), "test" : "a" }
> item = db.foo.findOne()
{ "_id" : ObjectId("4e93037bbf6f1dd3a0a9541a"), "test" : "a" }
> db.foo.update({"_id" :ObjectId("4e93037bbf6f1dd3a0a9541a") },{$set : ...
Getting URL hash location, and using it in jQuery
...Actually you don't need the :first pseudo-selector since you are using the ID selector, is assumed that IDs are unique within the DOM.
In case you want to get the hash from an URL string, you can use the String.substring method:
var url = "http://example.com/file.htm#foo";
var hash = url.substring...
MySQL Results as comma separated list
...
You can use GROUP_CONCAT to perform that, e.g. something like
SELECT p.id, p.name, GROUP_CONCAT(s.name) AS site_list
FROM sites s
INNER JOIN publications p ON(s.id = p.site_id)
GROUP BY p.id, p.name;
share
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Effect of a Bitwise Operator on a Boolean in Java
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Specifically, & and ^ and | are the non-short-circuit logical boolean operators.
– Ken
Nov 12 '09 at 18:36
1...
Extract substring using regexp in plain bash
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Very clean, and avoids calls to external programs.
– Victor Zamanian
Aug 2 '17 at 8:20
9
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Grepping a huge file (80GB) any way to speed it up?
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@elcortegano: That's what's called I/O redirection. Basically, it reads input from the following filename. Similar to cat file.sql | parallel ... but avoids a UUOC. GNU parallel also has a way to read input from a file using parallel ... :::: file.sql. ...
How to style SVG with external CSS?
..._In_HTML_Introduction
<html>
<body>
<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 56.69 56.69">
<g>
<path d="M28.44......./>
</g>
</svg>
</html>
If you ...
CSS I want a div to be on top of everything
...n div1-2.
.div {
}
#div1 {
z-index: 1;
position: absolute;
width: 500px;
height: 300px;
border: 1px solid black;
}
#div1-1 {
z-index: 2;
position: absolute;
left: 230px;
width: 200px;
height: 200px;
top: 31px;
background-color: indianred;
}
#div1-1-1 {
z-index: 3...
Removing an item from a select box
...query/2.1.1/jquery.min.js"></script>
<select name="selectBox" id="selectBox">
<option value="option1">option1</option>
<option value="option2">option2</option>
<option value="option3">option3</option>
<option value="option4">optio...
Get top 1 row of each group
...ITH cte AS
(
SELECT *,
ROW_NUMBER() OVER (PARTITION BY DocumentID ORDER BY DateCreated DESC) AS rn
FROM DocumentStatusLogs
)
SELECT *
FROM cte
WHERE rn = 1
If you expect 2 entries per day, then this will arbitrarily pick one. To get both entries for a day, use DENSE_RANK instead
As...