org.apache.iceberg.parquet

Class ParquetSchemaUtil

java.lang.Object

org.apache.iceberg.parquet.ParquetSchemaUtil

public class ParquetSchemaUtil
extends java.lang.Object

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ParquetSchemaUtil.HasIds

Method Summary

Modifier and Type	Method and Description
static org.apache.parquet.schema.MessageType	addFallbackIds(org.apache.parquet.schema.MessageType fileSchema)
static org.apache.parquet.schema.MessageType	applyNameMapping(org.apache.parquet.schema.MessageType fileSchema, NameMapping nameMapping)
static Schema	convert(org.apache.parquet.schema.MessageType parquetSchema) Converts a Parquet schema to an Iceberg schema.
static org.apache.parquet.schema.MessageType	convert(Schema schema, java.lang.String name)
static Schema	convertAndPrune(org.apache.parquet.schema.MessageType parquetSchema) Converts a Parquet schema to an Iceberg schema and prunes fields without IDs.
static boolean	hasIds(org.apache.parquet.schema.MessageType fileSchema)
static org.apache.parquet.schema.MessageType	pruneColumns(org.apache.parquet.schema.MessageType fileSchema, Schema expectedSchema)
static org.apache.parquet.schema.MessageType	pruneColumnsFallback(org.apache.parquet.schema.MessageType fileSchema, Schema expectedSchema) Prunes columns from a Parquet file schema that was written without field ids.

Methods inherited from class java.lang.Object

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

Method Detail

convert

public static org.apache.parquet.schema.MessageType convert(Schema schema,
                                                            java.lang.String name)

convert

public static Schema convert(org.apache.parquet.schema.MessageType parquetSchema)

Converts a Parquet schema to an Iceberg schema. Fields without IDs are kept and assigned fallback IDs.

Parameters:

parquetSchema - a Parquet schema

Returns:

a matching Iceberg schema for the provided Parquet schema

convertAndPrune

public static Schema convertAndPrune(org.apache.parquet.schema.MessageType parquetSchema)

Converts a Parquet schema to an Iceberg schema and prunes fields without IDs.

Parameters:

parquetSchema - a Parquet schema

Returns:

a matching Iceberg schema for the provided Parquet schema

pruneColumns

public static org.apache.parquet.schema.MessageType pruneColumns(org.apache.parquet.schema.MessageType fileSchema,
                                                                 Schema expectedSchema)

pruneColumnsFallback

public static org.apache.parquet.schema.MessageType pruneColumnsFallback(org.apache.parquet.schema.MessageType fileSchema,
                                                                         Schema expectedSchema)

Prunes columns from a Parquet file schema that was written without field ids.

Files that were written without field ids are read assuming that schema evolution preserved column order. Deleting columns was not allowed.

The order of columns in the resulting Parquet schema matches the Parquet file.

Parameters:

fileSchema - schema from a Parquet file that does not have field ids.

expectedSchema - expected schema

Returns:

a parquet schema pruned using the expected schema

hasIds

public static boolean hasIds(org.apache.parquet.schema.MessageType fileSchema)

addFallbackIds

public static org.apache.parquet.schema.MessageType addFallbackIds(org.apache.parquet.schema.MessageType fileSchema)

applyNameMapping

public static org.apache.parquet.schema.MessageType applyNameMapping(org.apache.parquet.schema.MessageType fileSchema,
                                                                     NameMapping nameMapping)