Package io.delta.kernel.internal.replay

Class LogReplay

Object

io.delta.kernel.internal.replay.LogReplay

public class LogReplay
extends Object

Replays a history of actions, resolving them to produce the current state of the table. The protocol for resolution is as follows: - The most recent AddFile and accompanying metadata for any `(path, dv id)` tuple wins. - RemoveFile deletes a corresponding AddFile. A RemoveFile "corresponds" to the AddFile that matches both the parquet file URI *and* the deletion vector's URI (if any). - The most recent Metadata wins. - The most recent Protocol version wins. - For each `(path, dv id)` tuple, this class should always output only one FileAction (either AddFile or RemoveFile) This class exposes the following public APIs - getProtocol(): latest non-null Protocol - getMetadata(): latest non-null Metadata - getAddFilesAsColumnarBatches(io.delta.kernel.engine.Engine, boolean, java.util.Optional<io.delta.kernel.expressions.Predicate>): return all active (not tombstoned) AddFiles as ColumnarBatchs

Field Summary

Fields

Modifier and Type	Field	Description
static int	ADD_FILE_DV_ORDINAL
static int	ADD_FILE_ORDINAL
static int	ADD_FILE_PATH_ORDINAL
static String	ADDFILE_FIELD_NAME
static final StructType	PROTOCOL_METADATA_READ_SCHEMA	Read schema when searching for the latest Protocol and Metadata.
static int	REMOVE_FILE_DV_ORDINAL
static int	REMOVE_FILE_ORDINAL
static int	REMOVE_FILE_PATH_ORDINAL
static String	REMOVEFILE_FIELD_NAME
static final StructType	SET_TRANSACTION_READ_SCHEMA	Read schema when searching for just the transaction identifiers
static String	SIDECAR_FIELD_NAME

Constructor Summary

Constructors

Constructor	Description
LogReplay(Path logPath, Path dataPath, long snapshotVersion, Engine engine, LogSegment logSegment, Optional<SnapshotHint> snapshotHint)

Method Summary

Modifier and Type	Method	Description
static boolean	containsAddOrRemoveFileActions(StructType schema)
CloseableIterator<FilteredColumnarBatch>	getAddFilesAsColumnarBatches(Engine engine, boolean shouldReadStats, Optional<Predicate> checkpointPredicate)	Returns an iterator of FilteredColumnarBatch representing all the active AddFiles in the table.
static StructType	getAddRemoveReadSchema(boolean shouldReadStats)	Read schema when searching for all the active AddFiles
Optional<Long>	getLatestTransactionIdentifier(Engine engine, String applicationId)
Metadata	getMetadata()
Protocol	getProtocol()
static StructType	withSidecarFileSchema(StructType schema)

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

PROTOCOL_METADATA_READ_SCHEMA

public static final StructType PROTOCOL_METADATA_READ_SCHEMA

Read schema when searching for the latest Protocol and Metadata.

SET_TRANSACTION_READ_SCHEMA

public static final StructType SET_TRANSACTION_READ_SCHEMA

Read schema when searching for just the transaction identifiers

SIDECAR_FIELD_NAME

public static String SIDECAR_FIELD_NAME

ADDFILE_FIELD_NAME

public static String ADDFILE_FIELD_NAME

REMOVEFILE_FIELD_NAME

public static String REMOVEFILE_FIELD_NAME

ADD_FILE_ORDINAL

public static int ADD_FILE_ORDINAL

ADD_FILE_PATH_ORDINAL

public static int ADD_FILE_PATH_ORDINAL

ADD_FILE_DV_ORDINAL

public static int ADD_FILE_DV_ORDINAL

REMOVE_FILE_ORDINAL

public static int REMOVE_FILE_ORDINAL

REMOVE_FILE_PATH_ORDINAL

public static int REMOVE_FILE_PATH_ORDINAL

REMOVE_FILE_DV_ORDINAL

public static int REMOVE_FILE_DV_ORDINAL

Constructor Details

LogReplay

public LogReplay(Path logPath,
 Path dataPath,
 long snapshotVersion,
 Engine engine,
 LogSegment logSegment,
 Optional<SnapshotHint> snapshotHint)

Method Details

withSidecarFileSchema

public static StructType withSidecarFileSchema(StructType schema)

containsAddOrRemoveFileActions

public static boolean containsAddOrRemoveFileActions(StructType schema)

getAddRemoveReadSchema

public static StructType getAddRemoveReadSchema(boolean shouldReadStats)

Read schema when searching for all the active AddFiles

getProtocol

public Protocol getProtocol()

getMetadata

public Metadata getMetadata()

getLatestTransactionIdentifier

public Optional<Long> getLatestTransactionIdentifier(Engine engine,
 String applicationId)

getAddFilesAsColumnarBatches

public CloseableIterator<FilteredColumnarBatch> getAddFilesAsColumnarBatches(Engine engine,
 boolean shouldReadStats,
 Optional<Predicate> checkpointPredicate)

Returns an iterator of FilteredColumnarBatch representing all the active AddFiles in the table.

Statistics are conditionally read for the AddFiles based on shouldReadStats. The returned batches have schema:

1. name: add

   type: AddFile.SCHEMA_WITH_STATS if shouldReadStats=true, otherwise AddFile.SCHEMA_WITHOUT_STATS