diff --git a/packages/tools/src/alterPlan.ts b/packages/tools/src/alterPlan.ts
index f4d9615fc..a1a8dfb78 100644
--- a/packages/tools/src/alterPlan.ts
+++ b/packages/tools/src/alterPlan.ts
@@ -337,14 +337,13 @@ export class AlterPlan {
             return opRes;
           }),
           op,
-        ];
-        // .filter(op => {
-        //   // filter duplicated drops
-        //   const existingDrop = this.operations.find(
-        //     o => o.operationType == 'dropConstraint' && o.oldObject === op['oldObject']
-        //   );
-        //   return existingDrop == null;
-        // })
+        ].filter(op => {
+          // filter duplicated drops
+          const existingDrop = this.operations.find(
+            o => o.operationType == 'dropConstraint' && o.oldObject === op['oldObject']
+          );
+          return existingDrop == null;
+        });
         return res;
       }