Don't delete databases that can be reused

zebra-state/src/config.rs

@@ -15,7 +15,7 @@ use tracing::Span;
 use zebra_chain::parameters::Network;
 
 use crate::{
-    constants::{DATABASE_FORMAT_VERSION_FILE_NAME, STATE_DATABASE_KIND},
+    constants::{DATABASE_FORMAT_VERSION_FILE_NAME, RESTORABLE_DB_VERSIONS, STATE_DATABASE_KIND},
     state_database_format_version_in_code, BoxError,
 };
 
@@ -317,6 +317,15 @@ fn check_and_delete_database(
         return None;
     }
 
+    // Don't delete databases that can be reused.
+    if RESTORABLE_DB_VERSIONS
+        .iter()
+        .map(|v| v - 1)
+        .any(|v| v == dir_major_version)
+    {
+        return None;
+    }
+
     let outdated_path = entry.path();
 
     // # Correctness