org.apache.drill.metastore.operate

Interface Metadata

All Known Implementing Classes:

IcebergMetadata, RdbmsMetadata

public interface Metadata

Provides Metastore component implementation metadata, including information about versioning support if any and current properties applicable to the Metastore component instance.

Field Summary

Fields

Modifier and Type	Field and Description
static int	UNDEFINED

Method Summary

Modifier and Type	Method and Description
default Map<String,String>	properties() Depending on Metastore component implementation, it may have properties.
boolean	supportsVersioning() Indicates if Metastore component supports versioning, i.e.
default long	version() Depending on Metastore component implementation, it may have version which can be used to determine if anything has changed during last call to the Metastore component.

Field Detail

UNDEFINED

static final int UNDEFINED

See Also:

Constant Field Values

Method Detail

supportsVersioning

boolean supportsVersioning()

Indicates if Metastore component supports versioning, i.e. Metastore component version is changed each time write operation is executed.

Returns:

true if Metastore component supports versioning, false otherwise

version

default long version()

Depending on Metastore component implementation, it may have version which can be used to determine if anything has changed during last call to the Metastore component. If Metastore component implementation, supports versioning, version is changed each time Metastore component data has changed. supportsVersioning() indicates if Metastore component supports versioning. If versioning is not supported, UNDEFINED is returned.

Returns:

current metastore version

properties

default Map<String,String> properties()

Depending on Metastore component implementation, it may have properties. If Metastore component supports properties, map with properties names and values are returned, otherwise empty map is returned.

Returns:

Metastore component implementation properties