title: R: sqlAppendTable only works with numbers?
body: <p>I am unable to get the R language DBI::sqlAppendTable function to work with anything other than numbers. Below is a bit of code illustrating the problem. I suspect the problem is that sqlAppendTable does not quote data. Any fix or workaround would be greatly appreciated.</p>
  
  <pre><code>num = data.frame(matrix(1:26, ncol=2))
  let = data.frame(matrix(letters, ncol=2))
  
  test.sqlAppendTable = function(dfr) {
      #dfr: A data frame.
      conx &lt;- dbConnect(RSQLite::SQLite(), ":memory:")
      on.exit(dbDisconnect(conx))
      dbWriteTable(conx, "temp", dfr[1:5, ])
      temp = dbReadTable(conx, 'temp')
      print(temp)
      sat = sqlAppendTable(conx, 'temp', dfr[6:10, ])
      print(sat)
      rs = dbExecute(conx, sat)
      cat('Result set (rs): ')
      print(rs)
      temp = dbReadTable(conx, 'temp')
      print(temp)
  }
  
  test.sqlAppendTable(num) #Runs fine.
  test.sqlAppendTable(let) #Generates error:
  #Error in rsqlite_send_query(conn@ptr, statement) : no such column: j
  </code></pre>