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Remove Primary Key in MySQL
...erty before dropping the key:
ALTER TABLE user_customer_permission MODIFY id INT NOT NULL;
ALTER TABLE user_customer_permission DROP PRIMARY KEY;
Note that you have a composite PRIMARY KEY which covers all three columns and id is not guaranteed to be unique.
If it happens to be unique, you can m...
Difference between and
...c A() {
System.out.println("creating bean A: " + this);
}
public void setBbb(B bbb) {
System.out.println("setting A.bbb with " + bbb);
this.bbb = bbb;
}
public void setCcc(C ccc) {
System.out.println("setting A.ccc with " + ccc);
this.ccc = ccc;
}
}
With the followin...
What is the difference between pluck and collect in Rails?
...particular field. See this.
When you do:
User.first.gifts.collect(&:id)
You have objects with all fields loaded and you simply get the id thanks to the method based on Enumerable.
So:
if you only need the id with Rails 4, use ids: User.first.gifts.ids
if you only need some fields with Ra...
How to use NSJSONSerialization
...
Your root json object is not a dictionary but an array:
[{"id": "1", "name":"Aaa"}, {"id": "2", "name":"Bbb"}]
This might give you a clear picture of how to handle it:
NSError *e = nil;
NSArray *jsonArray = [NSJSONSerialization JSONObjectWithData: data options: NSJSONReadingMutabl...
Get attribute name value of
...
Give your input an ID and use the attr method:
var name = $("#id").attr("name");
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REST Complex/Composite/Nested Resources [closed]
... (covers) may be cross-referenced. For example, you might also wish to provide references to authors, publishers , characters, or categories separately. You may wish to create these resources separately or before the comic book which references them as child resources. Alternatively, you may wish to...
How do I get the resource id of an image if I know its name?
How do I get the resource id of an image if I know its name (in Android)?
5 Answers
5
...
How to Create a circular progressbar in Android which rotates on it?
...ar.xml
<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
android:fromDegrees="270"
android:toDegrees="270">
<shape
android:innerRadiusRatio="2.5"
android:shape="ring"
android:thickness="1dp"
...
What is the difference between properties and attributes in HTML?
...a one-to-one relationship. For instance, for this HTML element:
<input id="the-input" type="text" value="Name:">
the corresponding DOM node will have id,type, and value properties (among others):
The id property is a reflected property for the id attribute: Getting the property reads the ...
Get next / previous element using JavaScript?
...ure javascript my thinking is that you would first have to collate them inside a collection.
var divs = document.getElementsByTagName("div");
//divs now contain each and every div element on the page
var selectionDiv = document.getElementById("MySecondDiv");
So basically with selectionDiv itera...