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/** Interface of a database in a catalog, and can be serialized along with Catalog. */
@PublicEvolving
public interface CatalogDatabase extends Serializable {

    ... ...

}

In the InMemoryCatalog scheme, in order to avoid the situation that the database does not exist when the table creation is executed on the JM side, we need to serialize the internal CatalogDatabase when serializing InMemoryCatalog, so the CatalogDatabase needs to extend Serializable.

Implementation Plan

The overall execution process is shown in the following figure.

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