Package org.apache.pinot.common.utils

Class DataSchema

java.lang.Object

org.apache.pinot.common.utils.DataSchema

public class DataSchema
extends Object

The DataSchema class describes the schema of DataTable.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	DataSchema.ColumnDataType

Field Summary

Fields

Modifier and Type	Field	Description
static DataSchema	EXPLAIN_RESULT_SCHEMA	Used by both Broker and Server to generate results for EXPLAIN PLAN queries.

Constructor Summary

Constructors

Constructor	Description
DataSchema(String[] columnNames, DataSchema.ColumnDataType[] columnDataTypes)

Method Summary

Modifier and Type	Method	Description
DataSchema	clone()
boolean	equals(Object anObject)
static DataSchema	fromBytes(ByteBuffer buffer)	This method use relative operations on the ByteBuffer and expects the buffer's position to be set correctly.
DataSchema.ColumnDataType	getColumnDataType(int index)
DataSchema.ColumnDataType[]	getColumnDataTypes()
String	getColumnName(int index)
String[]	getColumnNames()
DataSchema.ColumnDataType[]	getStoredColumnDataTypes()	Lazy compute the _storeColumnDataTypes field.
int	hashCode()
boolean	isTypeCompatibleWith(DataSchema anotherDataSchema)	Returns whether the given data schema is type compatible with this one.
int	size()
byte[]	toBytes()
String	toString()
static DataSchema	upgradeToCover(DataSchema originalSchema, DataSchema anotherDataSchema)	Upgrade the current data schema to cover the column data types in the given data schema.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

EXPLAIN_RESULT_SCHEMA

public static final DataSchema EXPLAIN_RESULT_SCHEMA

Used by both Broker and Server to generate results for EXPLAIN PLAN queries.

Constructor Detail

DataSchema

public DataSchema(String[] columnNames,
                  DataSchema.ColumnDataType[] columnDataTypes)

Method Detail

size

public int size()

getColumnName

public String getColumnName(int index)

getColumnNames

public String[] getColumnNames()

getColumnDataType

public DataSchema.ColumnDataType getColumnDataType(int index)

getColumnDataTypes

public DataSchema.ColumnDataType[] getColumnDataTypes()

getStoredColumnDataTypes

public DataSchema.ColumnDataType[] getStoredColumnDataTypes()

Lazy compute the _storeColumnDataTypes field.

isTypeCompatibleWith

public boolean isTypeCompatibleWith(DataSchema anotherDataSchema)

Returns whether the given data schema is type compatible with this one.

• All numbers are type compatible with each other
• Numbers are not type compatible with string
• Non-array types are not type compatible with array types

Parameters:

anotherDataSchema - Data schema to compare with

Returns:

Whether the two data schemas are type compatible

upgradeToCover

public static DataSchema upgradeToCover(DataSchema originalSchema,
                                        DataSchema anotherDataSchema)

Upgrade the current data schema to cover the column data types in the given data schema.

Data type LONG can cover INT and LONG.

Data type DOUBLE can cover all numbers, but with potential precision loss when use it to cover LONG.

NOTE: The given data schema should be type compatible with this one.

Parameters:

originalSchema - the original Data schema

anotherDataSchema - Data schema to cover

toBytes

public byte[] toBytes()
               throws IOException

Throws:

IOException

fromBytes

public static DataSchema fromBytes(ByteBuffer buffer)
                            throws IOException

This method use relative operations on the ByteBuffer and expects the buffer's position to be set correctly.

Throws:

IOException

clone

public DataSchema clone()

Overrides:

clone in class Object

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object anObject)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object