In an app I am working on, we use a MySQL database and want to store articles in a table. Rather than store them in a SQL DB, we were looking at just storing the key to the article in a NoSQL db. Is this a good problem to solve using NoSQL, or should we just create another table in MySQL and store the large amounts of text there?
We are looking at using MongoDB to store the text.
MongoDB is good at storing large blob-ish fields, whether text or binary. So I think that is a good thing to do.
There is a limit on BSON objects (MongoDB "records") of 4MB. If you text fields are larger than 4MB, you can use GridFS and then there is no limit.
First thing I'd do is check how MySQL runs with the 'large amount of data'. If you're getting acceptable performance, then there's no point trying to make the system more complicated.
Putting the text content into a separate table in MySQL wouldn't accomplish anything. Putting it into a separate DB might help, but I wouldn't do it unless you're sure that MySQL is a significant bottleneck, and that you can't do anything else, like optimize your queries.