title: Updating sql table in R using library(odbc) returns error: external pointer is not valid
body: <p>I am trying to perform:</p>
  
  <pre><code>con &lt;- dbConnect(odbc(),
                   Driver = "SQL Server",
                   Server = "myServer",
                   Database = "myDataBase",
                   UID = "myUser",
                   PWD = "myPassword")
  
  dbSendQuery(conn = con, 
              "INSERT INTO etl.VALOR_ETL (INTCODIGO,SERCODIGOEXTERNO,VALDATA,VALVALOR) 
               VALUES ('Generica', 'TESTE', '2018-01-01','2')" )
  </code></pre>
  
  <p>However, I get the following error:</p>
  
  <pre><code>Error in new_result(connection@ptr, statement) : 
  external pointer is not valid
  </code></pre>
  
  <p>I have tried other packages, however, I could not find any other one that allowed to query "insert into".</p>
  
  <p>What would be this issue related to?</p>