Interface SupportsNamespaces

  • All Known Implementing Classes:
    DynamoDbCatalog, GlueCatalog, HadoopCatalog, HiveCatalog, JdbcCatalog, NessieCatalog

    public interface SupportsNamespaces
    Catalog methods for working with namespaces.

    If an object such as a table, view, or function exists, its parent namespaces must also exist and must be returned by the discovery methods listNamespaces() and listNamespaces(Namespace namespace).

    Catalog implementations are not required to maintain the existence of namespaces independent of objects in a namespace. For example, a function catalog that loads functions using reflection and uses Java packages as namespaces is not required to support the methods to create, alter, or drop a namespace. Implementations are allowed to discover the existence of objects or namespaces without throwing NoSuchNamespaceException when no namespace is found.

    • Method Detail

      • createNamespace

        default void createNamespace​(Namespace namespace)
        Create a namespace in the catalog.
        Parameters:
        namespace - a namespace. Namespace.
        Throws:
        AlreadyExistsException - If the namespace already exists
        java.lang.UnsupportedOperationException - If create is not a supported operation
      • createNamespace

        void createNamespace​(Namespace namespace,
                             java.util.Map<java.lang.String,​java.lang.String> metadata)
        Create a namespace in the catalog.
        Parameters:
        namespace - a multi-part namespace
        metadata - a string Map of properties for the given namespace
        Throws:
        AlreadyExistsException - If the namespace already exists
        java.lang.UnsupportedOperationException - If create is not a supported operation
      • listNamespaces

        default java.util.List<Namespace> listNamespaces()
        List top-level namespaces from the catalog.

        If an object such as a table, view, or function exists, its parent namespaces must also exist and must be returned by this discovery method. For example, if table a.b.t exists, this method must return ["a"] in the result array.

        Returns:
        an List of namespace Namespace names
      • loadNamespaceMetadata

        java.util.Map<java.lang.String,​java.lang.String> loadNamespaceMetadata​(Namespace namespace)
                                                                              throws NoSuchNamespaceException
        Load metadata properties for a namespace.
        Parameters:
        namespace - a namespace. Namespace
        Returns:
        a string map of properties for the given namespace
        Throws:
        NoSuchNamespaceException - If the namespace does not exist (optional)
      • dropNamespace

        boolean dropNamespace​(Namespace namespace)
                       throws NamespaceNotEmptyException
        Drop a namespace. If the namespace exists and was dropped, this will return true.
        Parameters:
        namespace - a namespace. Namespace
        Returns:
        true if the namespace was dropped, false otherwise.
        Throws:
        NamespaceNotEmptyException - If the namespace is not empty
      • setProperties

        boolean setProperties​(Namespace namespace,
                              java.util.Map<java.lang.String,​java.lang.String> properties)
                       throws NoSuchNamespaceException
        Set a collection of properties on a namespace in the catalog.

        Properties that are not in the given map are not modified or removed by this method.

        Parameters:
        namespace - a namespace. Namespace
        properties - a collection of metadata to apply to the namespace
        Throws:
        NoSuchNamespaceException - If the namespace does not exist (optional)
        java.lang.UnsupportedOperationException - If namespace properties are not supported
      • removeProperties

        boolean removeProperties​(Namespace namespace,
                                 java.util.Set<java.lang.String> properties)
                          throws NoSuchNamespaceException
        Remove a set of property keys from a namespace in the catalog.

        Properties that are not in the given set are not modified or removed by this method.

        Parameters:
        namespace - a namespace. Namespace
        properties - a collection of metadata to apply to the namespace
        Throws:
        NoSuchNamespaceException - If the namespace does not exist (optional)
        java.lang.UnsupportedOperationException - If namespace properties are not supported
      • namespaceExists

        default boolean namespaceExists​(Namespace namespace)
        Checks whether the Namespace exists.
        Parameters:
        namespace - a namespace. Namespace
        Returns:
        true if the Namespace exists, false otherwise