Auto keep using rocksdb when it exists.

node/service/src/lib.rs

@@ -865,18 +865,30 @@ where
 			path.parent().ok_or(Error::DatabasePathRequired)?.into(),
 			crate::parachains_db::CacheSizes::default(),
 		)?,
-		DatabaseSource::Auto { paritydb_path, rocksdb_path, .. } =>
-			if paritydb_path.is_dir() && paritydb_path.exists() {
-				crate::parachains_db::open_creating_paritydb(
-					paritydb_path.parent().ok_or(Error::DatabasePathRequired)?.into(),
-					crate::parachains_db::CacheSizes::default(),
-				)?
+		DatabaseSource::Auto { paritydb_path, rocksdb_path, .. } => {
+			let paritydb_path_parent: std::path::PathBuf =
+				paritydb_path.parent().ok_or(Error::DatabasePathRequired)?.into();
+			if paritydb_path_parent.is_dir() && paritydb_path_parent.exists() {
+				let hybrid_parachains_path =
+					crate::parachains_db::rocksdb_parachain_path(paritydb_path);
+				if hybrid_parachains_path.is_dir() && hybrid_parachains_path.exists() {
+					crate::parachains_db::open_creating_rocksdb(
+						paritydb_path.clone(),
+						crate::parachains_db::CacheSizes::default(),
+					)?
+				} else {
+					crate::parachains_db::open_creating_paritydb(
+						paritydb_path_parent,
+						crate::parachains_db::CacheSizes::default(),
+					)?
+				}
 			} else {
 				crate::parachains_db::open_creating_rocksdb(
 					rocksdb_path.clone(),
 					crate::parachains_db::CacheSizes::default(),
 				)?
-			},
+			}
+		},
 		DatabaseSource::Custom { .. } => {
 			unimplemented!("No polkadot subsystem db for custom source.");
 		},

node/service/src/parachains_db/mod.rs

@@ -84,6 +84,13 @@ pub(crate) fn other_io_error(err: String) -> io::Error {
 	io::Error::new(io::ErrorKind::Other, err)
 }
 
+/// Path to the parachain rocksdb directory.
+/// `root` is the rocskdb default directory.
+#[cfg(feature = "full-node")]
+pub fn rocksdb_parachain_path(root: &PathBuf) -> PathBuf {
+	root.join("parachains").join("db")
+}
+
 /// Open the database on disk, creating it if it doesn't exist.
 #[cfg(feature = "full-node")]
 pub fn open_creating_rocksdb(
@@ -92,7 +99,7 @@ pub fn open_creating_rocksdb(
 ) -> io::Result<Arc<dyn Database>> {
 	use kvdb_rocksdb::{Database, DatabaseConfig};
 
-	let path = root.join("parachains").join("db");
+	let path = rocksdb_parachain_path(&root);
 
 	let mut db_config = DatabaseConfig::with_columns(columns::NUM_COLUMNS);