How to analyze row for row from MySQL?

I'm planning on using RapidMiner for my thesis, for which I need to analyze the sentiment of tweets.

What I have:
I have got a MySQL database with a table called "tweets", with columns [tweet_id, tweet_datetime, tweet_text, tweet_sentiment]. The table contains 1,3 million rows. The tweets are preprocessed (stopwords removed, words stemmed, etc.).

What I want:

• Read the "tweets" database into RapidMiner - done. I have a "Read Database" box in my process overview and it is connected properly
• Read the database row-by-row
• From each row, read tweet_text
• Analyze the sentiment of tweet_text using Bayesian filter
• The Bayesian filter should categorize into positive, neutral and negative
• Store the sentiment into the database in column tweet_sentiment
  

What my questions are:

• How can I feed the Naive Bayes operator one row at a time? I get only errors when connecting the Read Database box to the Naive Bayes box. There needs to be something in between I assume. Perhaps the Process Documents from Data operator?
• A Bayesian filter needs to be defined (define the categories) and manually trained. Can I train the Bayes filter in RapidMiner?
• I have downloaded a wordlist with positive and negative english words. I would like to feed these to the Bayes filter. Is this possible and how?
• How can I let RapidMiner store the outcome of the Bayes filter into the tweets database?

I don't expect all my questions to be answered. I am more than willing to figure things out for myself, but have a hard time starting. And most RapidMiner tutorials use data from other-than-databases. I would very much appreciate some pointers to get started here.