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What's the $unwind operator in MongoDB?
...f adding and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what the use case that you are trying to quote is saying. The example document from mongodb.org is as follows:
{
title : "this i...
Set value of hidden field in a form using jQuery's “.val()” doesn't work
I've been trying to set the value of a hidden field in a form using jQuery, but without success.
16 Answers
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Android add placeholder text to EditText
...Ah, ok. What you're looking for is setHint(int). Simply pass in a resource id of a string from your xml and you're good to go.
EDIT
And in XML, it's simply android:hint="someText"
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XPath to find elements that does not have an id or class
How can I get all tr elements without id attribute?
4 Answers
4
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When to use @QueryParam vs @PathParam
...ing up on general REST documentation and blog posts should give you some guidelines for a good way to structure API URLs. Most rest APIs tend to only have resource names and resource IDs in the path. Such as:
/departments/{dept}/employees/{id}
Some REST APIs use query strings for filtering, pagin...
How do I configure Maven for offline development?
...
Also consider you can use "mvn dependency:go-offline" to ensure all the dependencies referred to in your pom.xml are present in your local repository.
– Thorbjørn Ravn Andersen
May 3 '14 at 16:0...
Facebook database design?
...
Keep a friend table that holds the UserID and then the UserID of the friend (we will call it FriendID). Both columns would be foreign keys back to the Users table.
Somewhat useful example:
Table Name: User
Columns:
UserID PK
EmailAddress
Password
...
MongoDB SELECT COUNT GROUP BY
...er way to do it using aggregate:
db.contest.aggregate([
{"$group" : {_id:"$province", count:{$sum:1}}}
])
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MenuItemCompat.getActionView always returns null
...ry but the MenuItemCompat.getActionView always return null in every Android version I tested (4.2.2, 2.3.4 ....)
11 Answe...
JOIN queries vs multiple queries
...ins, multiple queries is much better... look at the following benchmark I did:
Single query with 5 Joins
query: 8.074508 seconds
result size: 2268000
5 queries in a row
combined query time: 0.00262 seconds
result size: 165 (6 + 50 + 7 + 12 + 90)
.
Note that we get the same results in both ...