MAPREDUCE-7368. DBOutputFormat.DBRecordWriter#write must throw except…

…ion when it fails

When the exception is caught and printed (instead of propagated) the consumer has no
way to tell write failed. This hides the failure and leads to problems which are
difficult to debug and at the same time can cause data corruption.

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/lib/db/DBOutputFormat.java

@@ -122,7 +122,7 @@ public void write(K key, V value) throws IOException {
         key.write(statement);
         statement.addBatch();
       } catch (SQLException e) {
-        e.printStackTrace();
+        throw new RuntimeException("Failed to execute SQL statement for key " + key, e);
       }
     }
   }