diff --git a/src/sql/upgrade-83.sql b/src/sql/upgrade-83.sql
new file mode 100644
index 00000000..01603e78
--- /dev/null
+++ b/src/sql/upgrade-83.sql
@@ -0,0 +1,3 @@
+-- This index was introduced in a migration but was never recorded in
+-- hydra.sql (the source of truth), which is why `if exists` is required.
+drop index if exists IndexBuildOutputsOnPath;