upserting.scala

import java.sql._
dataframe.coalesce("NUMBER OF WORKERS").mapPartitions((d) => Iterator(d)).foreach { batch =>
val dbc: Connection = DriverManager.getConnection("JDBCURL")
val st: PreparedStatement = dbc.prepareStatement("YOUR PREPARED STATEMENT")

batch.grouped("# Of Rows you want per batch").foreach { session =>
  session.foreach { x =>
    st.setDouble(1, x.getDouble(1)) 
    st.addBatch()
    }
  st.executeBatch()
  }
  dbc.close()
}