diff --git a/website/docs/reference/resource-configs/fail_calc.md b/website/docs/reference/resource-configs/fail_calc.md
index 6ee8e5f71ce..e78f7939cda 100644
--- a/website/docs/reference/resource-configs/fail_calc.md
+++ b/website/docs/reference/resource-configs/fail_calc.md
@@ -37,7 +37,7 @@ models:
         tests:
           - unique:
               config:
-                fail_calc: "sum(n_records)"
+                fail_calc: "case when count(*) > 0 then sum(n_records) else 0 end"
 ```
 
 </File>