Do not backup empty local database

Change-Id: I777cdf8103337270a1d491f6f9f465dcdcab2104
diff --git a/src/main/java/com/ericsson/gerrit/plugins/eventslog/sql/SQLStore.java b/src/main/java/com/ericsson/gerrit/plugins/eventslog/sql/SQLStore.java
index 7db9f64..ec32307 100644
--- a/src/main/java/com/ericsson/gerrit/plugins/eventslog/sql/SQLStore.java
+++ b/src/main/java/com/ericsson/gerrit/plugins/eventslog/sql/SQLStore.java
@@ -256,9 +256,7 @@
     if (!localDbExists) {
       return;
     }
-    if (copyLocal) {
-      copyFile();
-    }
+
     List<SQLEntry> entries;
     try {
       entries = localEventsDb.getAll();
@@ -273,6 +271,9 @@
       log.warn("Could not query all events from local", e);
     }
     try {
+      if (copyLocal) {
+        copyFile();
+      }
       localEventsDb.removeOldEvents(0);
     } catch (SQLException e) {
       log.warn("Could not destroy local database", e);