org.apache.drill.exec.record

Class SchemaUtil

java.lang.Object

org.apache.drill.exec.record.SchemaUtil

public class SchemaUtil
extends Object

Utility class for dealing with changing schemas

Constructor Summary

Constructors

Constructor and Description
SchemaUtil()

Method Summary

Modifier and Type	Method and Description
static VectorContainer	coerceContainer(VectorAccessible in, BatchSchema toSchema, BufferAllocator allocator)
static VectorContainer	coerceContainer(VectorAccessible in, BatchSchema toSchema, OperatorContext context) Creates a copy a record batch, converting any fields as necessary to coerce it into the provided schema
static TupleMetadata	fromBatchSchema(BatchSchema batchSchema)
static List<SchemaPath>	getSchemaPaths(TupleMetadata schema) Returns list of SchemaPath for fields taken from specified schema.
static BatchSchema	mergeSchemas(BatchSchema... schemas) Returns the merger of schemas.

Methods inherited from class java.lang.Object

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

Constructor Detail

SchemaUtil

public SchemaUtil()

Method Detail

mergeSchemas

public static BatchSchema mergeSchemas(BatchSchema... schemas)

Returns the merger of schemas. The merged schema will include the union all columns. If there is a type conflict between columns with the same schemapath but different types, the merged schema will contain a Union type.

Parameters:

schemas -

Returns:

coerceContainer

public static VectorContainer coerceContainer(VectorAccessible in,
                                              BatchSchema toSchema,
                                              OperatorContext context)

Creates a copy a record batch, converting any fields as necessary to coerce it into the provided schema

Parameters:

in -

toSchema -

context -

Returns:

coerceContainer

public static VectorContainer coerceContainer(VectorAccessible in,
                                              BatchSchema toSchema,
                                              BufferAllocator allocator)

fromBatchSchema

public static TupleMetadata fromBatchSchema(BatchSchema batchSchema)

getSchemaPaths

public static List<SchemaPath> getSchemaPaths(TupleMetadata schema)

Returns list of SchemaPath for fields taken from specified schema.

Parameters:

schema - the source of fields to return

Returns:

list of SchemaPath