diff --git a/rslib/src/storage/graves/mod.rs b/rslib/src/storage/graves/mod.rs
index b8d9c0021..468ea2811 100644
--- a/rslib/src/storage/graves/mod.rs
+++ b/rslib/src/storage/graves/mod.rs
@@ -72,7 +72,6 @@ impl SqliteStorage {
         Ok(graves)
     }
 
-    // fixme: graves is missing an index
     pub(crate) fn update_pending_grave_usns(&self, new_usn: Usn) -> Result<()> {
         self.db
             .prepare("update graves set usn=? where usn=-1")?
diff --git a/rslib/src/storage/upgrades/mod.rs b/rslib/src/storage/upgrades/mod.rs
index cb2b2ac81..6e9fe5b82 100644
--- a/rslib/src/storage/upgrades/mod.rs
+++ b/rslib/src/storage/upgrades/mod.rs
@@ -6,7 +6,7 @@ pub(super) const SCHEMA_MIN_VERSION: u8 = 11;
 /// The version new files are initially created with.
 pub(super) const SCHEMA_STARTING_VERSION: u8 = 11;
 /// The maximum schema version we can open.
-pub(super) const SCHEMA_MAX_VERSION: u8 = 17;
+pub(super) const SCHEMA_MAX_VERSION: u8 = 18;
 
 use super::SqliteStorage;
 use crate::err::Result;
@@ -35,9 +35,14 @@ impl SqliteStorage {
             self.upgrade_tags_to_schema17()?;
             self.db.execute_batch("update col set ver = 17")?;
         }
-        // fixme: on the next schema upgrade, change _collapsed to _expanded
-        // in DeckCommon and invert existing values, so that we can avoid
-        // serializing the values in the default case, and use
+        if ver < 18 {
+            self.db
+                .execute_batch(include_str!("schema18_upgrade.sql"))?;
+        }
+
+        // in some future schema upgrade, we may want to change
+        // _collapsed to _expanded in DeckCommon and invert existing values, so
+        // that we can avoid serializing the values in the default case, and use
         // DeckCommon::default() in new_normal() and new_filtered()
 
         Ok(())
@@ -46,6 +51,8 @@ impl SqliteStorage {
     pub(super) fn downgrade_to_schema_11(&self) -> Result<()> {
         self.begin_trx()?;
 
+        self.db
+            .execute_batch(include_str!("schema18_downgrade.sql"))?;
         self.downgrade_deck_conf_from_schema16()?;
         self.downgrade_decks_from_schema15()?;
         self.downgrade_notetypes_from_schema15()?;
diff --git a/rslib/src/storage/upgrades/schema18_downgrade.sql b/rslib/src/storage/upgrades/schema18_downgrade.sql
new file mode 100644
index 000000000..bd0eaa88e
--- /dev/null
+++ b/rslib/src/storage/upgrades/schema18_downgrade.sql
@@ -0,0 +1,15 @@
+ALTER TABLE graves
+  RENAME TO graves_old;
+CREATE TABLE graves (
+  usn integer NOT NULL,
+  oid integer NOT NULL,
+  type integer NOT NULL
+);
+INSERT INTO graves (usn, oid, type)
+SELECT usn,
+  oid,
+  type
+FROM graves_old;
+DROP TABLE graves_old;
+UPDATE col
+SET ver = 17;
\ No newline at end of file
diff --git a/rslib/src/storage/upgrades/schema18_upgrade.sql b/rslib/src/storage/upgrades/schema18_upgrade.sql
new file mode 100644
index 000000000..600676f46
--- /dev/null
+++ b/rslib/src/storage/upgrades/schema18_upgrade.sql
@@ -0,0 +1,18 @@
+ALTER TABLE graves
+  RENAME TO graves_old;
+CREATE TABLE graves (
+  oid integer NOT NULL,
+  type integer NOT NULL,
+  usn integer NOT NULL,
+  PRIMARY KEY (oid, type)
+) WITHOUT ROWID;
+INSERT
+  OR IGNORE INTO graves (oid, type, usn)
+SELECT oid,
+  type,
+  usn
+FROM graves_old;
+DROP TABLE graves_old;
+CREATE INDEX idx_graves_pending ON graves (usn);
+UPDATE col
+SET ver = 18;
\ No newline at end of file