org.yamcs.yarch

Class TableDefinition

java.lang.Object

org.yamcs.yarch.TableDefinition

public class TableDefinition
extends Object

A table definition consists of a (key,value) pair of tuple definitions. A tuple has to contain all the columns from the key while it can contain only a few of the columns from the value (basically it's a sparse table). The key is encoded as a bytestream of all the columns in order The value is encoded as a bytestream of all the columns prceded by their index. A table can also be partitioned in multiple files on disc, according to the partitioningSpec.

Author:

nm

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	TableDefinition.PartitionStorage

Field Summary

Fields

Modifier and Type	Field and Description
static int	CURRENT_FORMAT_VERSION

Constructor Summary

Constructors

Constructor and Description
TableDefinition(String name, TupleDefinition tdef, List<String> primaryKey) Used when creating an "empty"(i.e.

Method Summary

Modifier and Type	Method and Description
Short	addAndGetEnumValue(String columnName, String value) get the enum value corresponding to a column, creating it if it does not exist
void	changeFormatDefinition(int formatVersion) Changes the formatVersion and serializes the table definition to disk
Tuple	deserialize(byte[] k, byte[] v)
ColumnDefinition	getColumnDefinition(String cname)
ColumnSerializer	getColumnSerializer(String columnName)
String	getDataDir()
com.google.common.collect.BiMap<String,Short>	getEnumValues(String columnName)
int	getFormatVersion()
List<String>	getHistogramColumns()
TupleDefinition	getKeyDefinition()
String	getName()
PartitioningSpec	getPartitioningSpec()
TableDefinition.PartitionStorage	getPartitionStorage()
String	getStorageEngineName()
TupleDefinition	getTupleDefinition()
TupleDefinition	getValueDefinition()
boolean	hasCustomDataDir()
boolean	hasHistogram()
boolean	hasPartitioning()
boolean	isCompressed()
boolean	isIndexedByKey(String cname)
boolean	isPartitionedByValue()
void	renameColumn(String oldName, String newName) Renames column and serializes the table definition to disk.
byte[]	serializeKey(Tuple t) Transforms the key part of the tuple into a byte array to be written to disk.
byte[]	serializeValue(Tuple t) Transform the value part of the tuple into a byte array to be written on disk.
void	setCompressed(boolean compressed)
void	setCustomDataDir(boolean customDataDir) sets the customDataDir - if true, the dataDir will not be discarded after serialisation, so the next time the server is restarted it will stay to the set value.
void	setDataDir(String dataDir) sets dataDir to this value
void	setDb(YarchDatabase ydb)
void	setHistogramColumns(List<String> histoColumns)
void	setName(String name)
void	setPartitioningSpec(PartitioningSpec pspec) time based partitions can be on the first column of the key (which has to be of type timestamp) value based partitions can be on any other mandatory column
void	setPartitionStorage(TableDefinition.PartitionStorage partitionStorage)
void	setStorageEngineName(String storageEngineName)
String	toString()
void	validate() Checks that the table definition is valid: - primary key not string, except for the last in the list (otherwise the binary sorting does not work properly)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

CURRENT_FORMAT_VERSION

public static int CURRENT_FORMAT_VERSION

Constructor Detail

TableDefinition

public TableDefinition(String name,
                       TupleDefinition tdef,
                       List<String> primaryKey)
                throws StreamSqlException

Used when creating an "empty"(i.e. no enum values) table via sql.

Parameters:

name -

tdef -

primaryKey -

Throws:

StreamSqlException

Method Detail

setDb

public void setDb(YarchDatabase ydb)

setPartitioningSpec

public void setPartitioningSpec(PartitioningSpec pspec)
                         throws StreamSqlException

time based partitions can be on the first column of the key (which has to be of type timestamp) value based partitions can be on any other mandatory column

Parameters:

pspec -

Throws:

StreamSqlException

getKeyDefinition

public TupleDefinition getKeyDefinition()

getValueDefinition

public TupleDefinition getValueDefinition()

getName

public String getName()

setName

public void setName(String name)

setCustomDataDir

public void setCustomDataDir(boolean customDataDir)

sets the customDataDir - if true, the dataDir will not be discarded after serialisation, so the next time the server is restarted it will stay to the set value. - if false, at restart the dataDir will be set to the YarchDatabase.dataDir

Parameters:

customDataDir -

hasCustomDataDir

public boolean hasCustomDataDir()

getDataDir

public String getDataDir()

setDataDir

public void setDataDir(String dataDir)

sets dataDir to this value

Parameters:

dataDir -

getTupleDefinition

public TupleDefinition getTupleDefinition()

validate

public void validate()
              throws StreamSqlException

Checks that the table definition is valid: - primary key not string, except for the last in the list (otherwise the binary sorting does not work properly)

Throws:

StreamSqlException

serializeKey

public byte[] serializeKey(Tuple t)

Transforms the key part of the tuple into a byte array to be written to disk. The tuple must contain each column from the key and they are written in order (such that sorting is according to the definition of the primary key).

Parameters:

t -

Returns:

changeFormatDefinition

public void changeFormatDefinition(int formatVersion)

Changes the formatVersion and serializes the table definition to disk

Parameters:

formatVersion - new format version

renameColumn

public void renameColumn(String oldName,
                         String newName)

Renames column and serializes the table definition to disk. Should not be used when the table is in used (e.g. by a table writer or reader).

Parameters:

oldName - - old name of the column

newName - - new name of the column

addAndGetEnumValue

public Short addAndGetEnumValue(String columnName,
                                String value)

get the enum value corresponding to a column, creating it if it does not exist

Returns:

serializeValue

public byte[] serializeValue(Tuple t)

Transform the value part of the tuple into a byte array to be written on disk. Each column is preceded by a tag (the column index). If there are columns in the tuple which are not in the valueDef, they are added and the TableDefinition is serialized on disk.

Parameters:

t -

Returns:

deserialize

public Tuple deserialize(byte[] k,
                         byte[] v)

isCompressed

public boolean isCompressed()

isIndexedByKey

public boolean isIndexedByKey(String cname)

Parameters:

cname - the column name

Returns:

true if cname is the first column of the key

getColumnDefinition

public ColumnDefinition getColumnDefinition(String cname)

hasPartitioning

public boolean hasPartitioning()

getPartitioningSpec

public PartitioningSpec getPartitioningSpec()

setCompressed

public void setCompressed(boolean compressed)

setHistogramColumns

public void setHistogramColumns(List<String> histoColumns)
                         throws StreamSqlException

Throws:

StreamSqlException

hasHistogram

public boolean hasHistogram()

getEnumValues

public com.google.common.collect.BiMap<String,Short> getEnumValues(String columnName)

getHistogramColumns

public List<String> getHistogramColumns()

toString

public String toString()

Overrides:

toString in class Object

getColumnSerializer

public ColumnSerializer getColumnSerializer(String columnName)

getStorageEngineName

public String getStorageEngineName()

setStorageEngineName

public void setStorageEngineName(String storageEngineName)

getPartitionStorage

public TableDefinition.PartitionStorage getPartitionStorage()

setPartitionStorage

public void setPartitionStorage(TableDefinition.PartitionStorage partitionStorage)

isPartitionedByValue

public boolean isPartitionedByValue()

getFormatVersion

public int getFormatVersion()