diff --git a/bin/mongodb/clas_index.js b/bin/mongodb/clas_index.js
new file mode 100644
index 0000000000..da1675a182
--- /dev/null
+++ b/bin/mongodb/clas_index.js
@@ -0,0 +1,3 @@
+db.clas_clas.ensureIndex({teachers:1,viewedAt:-1})
+db.clas_student.ensureIndex({clasId:1,userId:1})
+db.clas_student.ensureIndex({userId:1},{ partialFilterExpression: { managed: true } })