diff --git a/docs/content/engines/spark.md b/docs/content/engines/spark.md
index 1b2d2f1a4d2e..4d9983c051f2 100644
--- a/docs/content/engines/spark.md
+++ b/docs/content/engines/spark.md
@@ -569,8 +569,8 @@ s
       <td>
          To expire snapshots. Argument:
             <li>table: the target table identifier. Cannot be empty.</li>
-            <li>retainMax: the maximum number of completed snapshots to retain.</li>
-            <li>retainMin: the minimum number of completed snapshots to retain.</li>
+            <li>retain_max: the maximum number of completed snapshots to retain.</li>
+            <li>retain_min: the minimum number of completed snapshots to retain.</li>
             <li>older_than: timestamp before which snapshots will be removed.</li>
             <li>max_deletes: the maximum number of snapshots that can be deleted at once.</li>
       </td>