diff --git a/src/pkg/exp/sql/driver/driver.go b/src/pkg/exp/sql/driver/driver.go
index 35fc6ae43c..9fc47905ce 100644
--- a/src/pkg/exp/sql/driver/driver.go
+++ b/src/pkg/exp/sql/driver/driver.go
@@ -138,6 +138,8 @@ type Rows interface {
 	// The dest slice may be populated with only with values
 	// of subset types defined above, but excluding string.
 	// All string values must be converted to []byte.
+	//
+	// Next should return io.EOF when there are no more rows.
 	Next(dest []interface{}) error
 }