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belongs_to through associations
...tion cannot have a :through option. You're better off caching the question_id on Choice and adding a unique index to the table (especially because validates_uniqueness_of is prone to race conditions).
If you're paranoid, add a custom validation to Choice that confirms that the answer's question_id ...
Only one expression can be specified in the select list when the subquery is not introduced with EXI
...(or multiple) columns in your subquery to do the comparison in the WHERE A_ID IN (subquery) clause - which column is it supposed to compare A_ID to? Your subquery must only return the one column needed for the comparison to the column on the other side of the IN. So the query needs to be of the form...
Format of the initialization string does not conform to specification starting at index 0
...r 2012
Standard Security
Server=myServerAddress;Database=myDataBase;User Id=myUsername;Password=myPassword;
Trusted Connection
Server=myServerAddress;Database=myDataBase;Trusted_Connection=True;
Connection to a SQL Server instance
The server/instance name syntax used in the server option is ...
Changing the image source using jQuery
...You can use jQuery's attr() function. For example, if your img tag has an id attribute of 'my_image', you would do this:
<img id="my_image" src="first.jpg"/>
Then you can change the src of your image with jQuery like this:
$("#my_image").attr("src","second.jpg");
To attach this to a cli...
How do you query for “is not null” in Mongo?
...ue. This includes documents that do not contain the field.
So in your provided case following query going to return all the documents with imageurl field exists and having not null value:
db.mycollection.find({ 'imageurl' : { $exists: true, $ne: null } });
...
Android - shadow on text?
I am wondering how to add shadow on text in android?
6 Answers
6
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Design for Facebook authentication in an iOS app that also accesses a secured web service
... to register for an account with you entirely separate from their Facebook ID, right? Then some other time they log in with Facebook.... And you just created them a second account and lost their first one.
There needs to be a way to be logged in to your web service, then log in to facebook, and ca...
Is it possible to update a localized storyboard's strings?
...e
Visit for more info: https://conyac.cc/business/columns/localization_guide_ios
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Good PHP ORM Library?
...works well with Symfony. However if you're looking for database support besides the main ones you'll have to write your own code.
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Securely storing environment variables in GAE with app.yaml
...ource code as it will be checked into source control. The wrong people (inside or outside your organization) may find it there. Also, your development environment probably uses different config values from your production environment. If these values are stored in code, you will have to run differen...