diff --git a/scripts/lua/modules/timeseries/drivers/rrd.lua b/scripts/lua/modules/timeseries/drivers/rrd.lua
index 4cb877acbe..1c65080431 100644
--- a/scripts/lua/modules/timeseries/drivers/rrd.lua
+++ b/scripts/lua/modules/timeseries/drivers/rrd.lua
@@ -1107,7 +1107,7 @@ function driver:queryTotal(schema, tstart, tend, tags, options)
     local totals = {}
 
     local serie_idx = 0
-    for _, _ in pairs(fdata) do
+    for _, _ in pairs(fdata or {}) do
         serie_idx = serie_idx + 1 -- the first id is 1
         local name = schema._metrics[serie_idx]
         local fdata_name = names[serie_idx]