org.apache.drill.exec.record.metadata

Class SchemaBuilder

java.lang.Object

org.apache.drill.exec.record.metadata.SchemaBuilder

public class SchemaBuilder
extends Object

Builder of a row set schema expressed as a list of materialized fields. Optimized for use when creating schemas by hand in tests.

Example usage to create the following schema:
(c: INT, a: MAP(b: VARCHAR, d: INT, e: MAP(f: VARCHAR), g: INT), h: UNION(INT, MAP(h1: INT), LIST(BIGINT)), i: BIGINT[], j: VARCHAR[][][])

Code:

     TupleMetadata schema = new SchemaBuilder()
        .add("c", MinorType.INT)
        .addMap("a")
          .addNullable("b", MinorType.VARCHAR)
          .add("d", MinorType.INT)
          .addMap("e") // or .addMapArray("e")
            .add("f", MinorType.VARCHAR)
            .resumeMap()
          .add("g", MinorType.INT)
          .resumeSchema()
        .addUnion("h") // or .addList("h")
          .addType(MinorType.INT)
          .addMap()
            .add("h1", MinorType.INT)
            .resumeUnion()
          .addList()
            .addType(MinorType.BIGINT)
            .resumeUnion()
          .resumeSchema()
        .addArray("i", MinorType.BIGINT)
        .addRepeatedList("j")
          .addDimension()
            .addArray(MinorType.VARCHAR)
            .resumeList()
         .resumeSchema()
        .buildSchema();
 

Constructor Summary

Constructors

Constructor and Description
SchemaBuilder()

Method Summary

Modifier and Type	Method and Description
SchemaBuilder	add(ColumnMetadata column)
SchemaBuilder	add(MaterializedField col)
SchemaBuilder	add(String name, TypeProtos.MajorType type)
SchemaBuilder	add(String name, TypeProtos.MinorType type)
SchemaBuilder	add(String name, TypeProtos.MinorType type, int width)
SchemaBuilder	add(String name, TypeProtos.MinorType type, int precision, int scale)
SchemaBuilder	add(String name, TypeProtos.MinorType type, TypeProtos.DataMode mode)
SchemaBuilder	addAll(TupleMetadata from)
SchemaBuilder	addArray(String name, TypeProtos.MinorType type)
SchemaBuilder	addArray(String name, TypeProtos.MinorType type, int dims) Add a multi-dimensional array, implemented as a repeated vector along with 0 or more repeated list vectors.
SchemaBuilder	addArray(String name, TypeProtos.MinorType type, int precision, int scale)
void	addColumn(ColumnMetadata column)
SchemaBuilder	addDecimal(String name, TypeProtos.MinorType type, TypeProtos.DataMode mode, int precision, int scale)
DictBuilder	addDict(String name, TypeProtos.MajorType keyType)
DictBuilder	addDict(String name, TypeProtos.MinorType keyType)
DictBuilder	addDictArray(String name, TypeProtos.MajorType keyType)
DictBuilder	addDictArray(String name, TypeProtos.MinorType keyType)
SchemaBuilder	addDynamic(String name)
UnionBuilder	addList(String name)
MapBuilder	addMap(String name) Add a map column.
MapBuilder	addMapArray(String name)
SchemaBuilder	addNullable(String name, TypeProtos.MinorType type)
SchemaBuilder	addNullable(String name, TypeProtos.MinorType type, int width)
SchemaBuilder	addNullable(String name, TypeProtos.MinorType type, int precision, int scale)
RepeatedListBuilder	addRepeatedList(String name)
UnionBuilder	addUnion(String name)
TupleMetadata	build()
TupleMetadata	buildSchema()
static MaterializedField	columnSchema(String name, TypeProtos.MinorType type, TypeProtos.DataMode mode) Create a column schema using the "basic three" properties of name, type and cardinality (AKA "data mode.") Use the ColumnBuilder for to set other schema attributes.

Methods inherited from class java.lang.Object

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

Constructor Detail

SchemaBuilder

public SchemaBuilder()

Method Detail

columnSchema

public static MaterializedField columnSchema(String name,
                                             TypeProtos.MinorType type,
                                             TypeProtos.DataMode mode)

Create a column schema using the "basic three" properties of name, type and cardinality (AKA "data mode.") Use the ColumnBuilder for to set other schema attributes. Name is relative to the enclosing map or tuple; it is not the fully qualified path name.

addColumn

public void addColumn(ColumnMetadata column)

add

public SchemaBuilder add(String name,
                         TypeProtos.MajorType type)

add

public SchemaBuilder add(MaterializedField col)

add

public SchemaBuilder add(ColumnMetadata column)

add

public SchemaBuilder add(String name,
                         TypeProtos.MinorType type,
                         TypeProtos.DataMode mode)

add

public SchemaBuilder add(String name,
                         TypeProtos.MinorType type)

add

public SchemaBuilder add(String name,
                         TypeProtos.MinorType type,
                         int width)

add

public SchemaBuilder add(String name,
                         TypeProtos.MinorType type,
                         int precision,
                         int scale)

addNullable

public SchemaBuilder addNullable(String name,
                                 TypeProtos.MinorType type)

addNullable

public SchemaBuilder addNullable(String name,
                                 TypeProtos.MinorType type,
                                 int width)

addNullable

public SchemaBuilder addNullable(String name,
                                 TypeProtos.MinorType type,
                                 int precision,
                                 int scale)

addArray

public SchemaBuilder addArray(String name,
                              TypeProtos.MinorType type)

addArray

public SchemaBuilder addArray(String name,
                              TypeProtos.MinorType type,
                              int precision,
                              int scale)

addDecimal

public SchemaBuilder addDecimal(String name,
                                TypeProtos.MinorType type,
                                TypeProtos.DataMode mode,
                                int precision,
                                int scale)

addArray

public SchemaBuilder addArray(String name,
                              TypeProtos.MinorType type,
                              int dims)

Add a multi-dimensional array, implemented as a repeated vector along with 0 or more repeated list vectors.

Parameters:

name - column name

type - base data type

dims - number of dimensions, 1 or more

Returns:

this builder

addDynamic

public SchemaBuilder addDynamic(String name)

addAll

public SchemaBuilder addAll(TupleMetadata from)

addMap

public MapBuilder addMap(String name)

Add a map column. The returned schema builder is for the nested map. Building that map, using MapBuilder.resumeSchema(), will return the original schema builder.

Parameters:

name - the name of the map column

Returns:

a builder for the map

addMapArray

public MapBuilder addMapArray(String name)

addDict

public DictBuilder addDict(String name,
                           TypeProtos.MinorType keyType)

addDict

public DictBuilder addDict(String name,
                           TypeProtos.MajorType keyType)

addDictArray

public DictBuilder addDictArray(String name,
                                TypeProtos.MinorType keyType)

addDictArray

public DictBuilder addDictArray(String name,
                                TypeProtos.MajorType keyType)

addUnion

public UnionBuilder addUnion(String name)

addList

public UnionBuilder addList(String name)

addRepeatedList

public RepeatedListBuilder addRepeatedList(String name)

buildSchema

public TupleMetadata buildSchema()

build

public TupleMetadata build()