diff --git a/src/matrix/storage/idb/schema.js b/src/matrix/storage/idb/schema.js
index aeb85a4b..3af31d8d 100644
--- a/src/matrix/storage/idb/schema.js
+++ b/src/matrix/storage/idb/schema.js
@@ -2,6 +2,7 @@ import {iterateCursor, reqAsPromise} from "./utils.js";
 import {RoomMember, EVENT_TYPE as MEMBER_EVENT_TYPE} from "../../room/members/RoomMember.js";
 import {RoomMemberStore} from "./stores/RoomMemberStore.js";
 import {SessionStore} from "./stores/SessionStore.js";
+import {encodeScopeTypeKey} from "./stores/OperationStore.js";
 
 // FUNCTIONS SHOULD ONLY BE APPENDED!!
 // the index in the array is the database version
@@ -14,6 +15,7 @@ export const schema = [
     createAccountDataStore,
     createInviteStore,
     createArchivedRoomSummaryStore,
+    migrateOperationScopeIndex,
 ];
 // TODO: how to deal with git merge conflicts of this array?
 
@@ -114,4 +116,23 @@ function createInviteStore(db) {
 // v8
 function createArchivedRoomSummaryStore(db) {
     db.createObjectStore("archivedRoomSummary", {keyPath: "summary.roomId"});
+}
+
+// v9
+async function migrateOperationScopeIndex(db, txn) {
+    try {
+        const operations = txn.objectStore("operations");
+        operations.deleteIndex("byTypeAndScope");
+        await iterateCursor(operations.openCursor(), (op, key, cur) => {
+            const {typeScopeKey} = op;
+            delete op.typeScopeKey;
+            const [type, scope] = typeScopeKey.split("|");
+            op.scopeTypeKey = encodeScopeTypeKey(scope, type);
+            cur.update(op);
+        });
+        operations.createIndex("byScopeAndType", "scopeTypeKey", {unique: false});
+    } catch (err) {
+        txn.abort();
+        console.error("could not migrate operations", err.stack);
+    }
 }
\ No newline at end of file
diff --git a/src/matrix/storage/idb/stores/OperationStore.js b/src/matrix/storage/idb/stores/OperationStore.js
index 47207cc4..4d101430 100644
--- a/src/matrix/storage/idb/stores/OperationStore.js
+++ b/src/matrix/storage/idb/stores/OperationStore.js
@@ -14,8 +14,8 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-function encodeTypeScopeKey(type, scope) {
-    return `${type}|${scope}`;
+export function encodeScopeTypeKey(scope, type) {
+    return `${scope}|${type}`;
 }
 
 export class OperationStore {
@@ -28,10 +28,10 @@ export class OperationStore {
     }
 
     async getAllByTypeAndScope(type, scope) {
-        const key = encodeTypeScopeKey(type, scope);
+        const key = encodeScopeTypeKey(scope, type);
         const results = [];
-        await this._store.index("byTypeAndScope").iterateWhile(key, value => {
-            if (value.typeScopeKey !== key) {
+        await this._store.index("byScopeAndType").iterateWhile(key, value => {
+            if (value.scopeTypeKey !== key) {
                 return false;
             }
             results.push(value);
@@ -41,7 +41,7 @@ export class OperationStore {
     }
 
     add(operation) {
-        operation.typeScopeKey = encodeTypeScopeKey(operation.type, operation.scope);
+        operation.scopeTypeKey = encodeScopeTypeKey(operation.scope, operation.type);
         this._store.add(operation);
     }