diff --git a/frontend/src/pages/SqlExplorer.tsx b/frontend/src/pages/SqlExplorer.tsx
index 659f36f..241b7c7 100644
--- a/frontend/src/pages/SqlExplorer.tsx
+++ b/frontend/src/pages/SqlExplorer.tsx
@@ -163,9 +163,11 @@ export function SqlExplorerPage() {
     : [];
 
   // Custom tooltip that shows all row values on hover
-  const renderTooltip = (props: { active?: boolean; payload?: Array<{ payload: Record<string, unknown> }> }) => {
-    if (!props.active || !props.payload?.length || !result) return null;
-    const data = props.payload[0].payload;
+  const renderTooltip = ({ active, payload }: Record<string, unknown>) => {
+    if (!active || !result) return null;
+    const items = payload as Array<{ payload: Record<string, unknown> }> | undefined;
+    if (!items?.length) return null;
+    const data = items[0].payload;
     return (
       <div className="rounded-lg border border-surface-700 bg-surface-900 px-3 py-2 text-xs shadow-lg">
         {result.columns.map((col, i) => {