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+# Data Node
+
+DataNode is the component to write insert and delete messages into persistent blob storage, for example minIO or S3.
+
+## Dependency
+
+- KV store: a kv store that persists messages into blob storage.
+- Message stream: receive messages and publish imformation
+- Root Coordinator: get the latest unique IDs.
+- Data Coordinator: get the flush information and which message stream to subscribe.