upsert.scala

import java.sql._

// Start with a DataFrame and lower the number of coalesce to the number of machines I have
dataframe.coalesce(4).mapPartitions ((d) => Iterator (d) ).foreach {
  batch => // Per parition, create a JDBC connection
    val dbc: Connection = DriverManager.getConnection ("JDBCURL")
    val st: PreparedStatement = dbc.prepareStatement ("YOUR PREPARED STATEMENT")
    // Within the partition figure out what batch I'd like to write to MySQL
    batch.grouped ("# Of Rows you want per batch").foreach {
      session => // Add each of those
        session.foreach {
          x =>
            st.setDouble (1, x.getDouble (1) )
            st.addBatch ()
        }
        // Execute batch command
        st.executeBatch ()
    }
    // Close the connection
    dbc.close ()
}