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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...
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...
How to get RelativeLayout working with merge and include?
...oogle.com/issues/36908001
To fix it, make sure you overwrite BOTH layout_width and layout_height when including, otherwise everything will be ignored.
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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...
MySQL ON DUPLICATE KEY - last insert id?
...e.html
At the bottom of the page they explain how you can make LAST_INSERT_ID meaningful for updates by passing an expression to that MySQL function.
From the MySQL documentation example:
If a table contains an AUTO_INCREMENT column and INSERT ... UPDATE inserts a row, the LAST_INSERT_ID() func...
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 attribute name value of
...
Give your input an ID and use the attr method:
var name = $("#id").attr("name");
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Cookie overflow in rails application?
...session'
UPDATE:
If anyone is receiving a null value in column "session_id" violates not-null constraint message in rails 4, there's a workaround in github(not tested). You must to create an initializer with ActiveRecord::SessionStore::Session.attr_accessible :data, :session_id
...
schema builder laravel migrations unique on two columns
...ique key across multiple columns.
$table->unique(array('mytext', 'user_id'));
or (a little neater)
$table->unique(['mytext', 'user_id']);
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Java lib or app to convert CSV to XML file? [closed]
...tworks.xstream.XStream;
public class CsvToXml {
public static void main(String[] args) {
String startFile = "./startData.csv";
String outFile = "./outData.xml";
try {
CSVReader reader = new CSVReader(new FileReader(startFile));
String[] li...