diff --git a/superset/connectors/sqla/models.py b/superset/connectors/sqla/models.py
index f894496dcff..b25d09bceb2 100644
--- a/superset/connectors/sqla/models.py
+++ b/superset/connectors/sqla/models.py
@@ -721,6 +721,9 @@ class SqlaTable(Model, BaseDatasource):
         groupby_exprs_sans_timestamp: OrderedDict = OrderedDict()
 
         if groupby:
+            # dedup columns while preserving order
+            groupby = list(dict.fromkeys(groupby))
+
             select_exprs = []
             for s in groupby:
                 if s in cols:
diff --git a/superset/viz.py b/superset/viz.py
index b6d89fbda23..8cbb2ecdf99 100644
--- a/superset/viz.py
+++ b/superset/viz.py
@@ -970,6 +970,10 @@ class BubbleViz(NVD3Viz):
         d["groupby"] = [form_data.get("entity")]
         if form_data.get("series"):
             d["groupby"].append(form_data.get("series"))
+
+        # dedup groupby if it happens to be the same
+        d["groupby"] = list(dict.fromkeys(d["groupby"]))
+
         self.x_metric = form_data.get("x")
         self.y_metric = form_data.get("y")
         self.z_metric = form_data.get("size")