Package org.apache.calcite.sql.type

Class SqlTypeTransforms

java.lang.Object

org.apache.calcite.sql.type.SqlTypeTransforms

public abstract class SqlTypeTransforms
extends Object

SqlTypeTransforms defines a number of reusable instances of SqlTypeTransform.

NOTE: avoid anonymous inner classes here except for unique, non-generalizable strategies; anything else belongs in a reusable top-level class. If you find yourself copying and pasting an existing strategy's anonymous inner class, you're making a mistake.

Field Summary

Fields

Modifier and Type	Field	Description
static final SqlTypeTransform	FORCE_NULLABLE	Parameter type-inference transform strategy where a derived type is transformed into the same type with nulls allowed.
static final SqlTypeTransform	FROM_MEASURE	Parameter type-inference transform that transforms MEASURE<T> to T for some type T.
static final SqlTypeTransform	LEAST_NULLABLE	Type-inference strategy whereby the result is NOT NULL if any of the arguments is NOT NULL; otherwise the type is unchanged.
static final SqlTypeTransform	ONLY_COLUMN	Parameter type-inference transform strategy where a derived type must be a struct type with precisely one field and the returned type is the type of that field.
static final SqlTypeTransform	TO_ARRAY	Parameter type-inference transform strategy that wraps a given type in a array.
static final SqlTypeTransform	TO_ARRAY_QUERY	Parameter type-inference transform strategy that wraps a given type in an array or wraps a field of the given type in an array if the given type is struct with one field.
static final SqlTypeTransform	TO_MAP	Parameter type-inference transform strategy that converts a two-field record type to a MAP type.
static final SqlTypeTransform	TO_MEASURE	Parameter type-inference transform that transforms T to MEASURE<T> for some type T.
static final SqlTypeTransform	TO_MULTISET	Parameter type-inference transform strategy that wraps a given type in a multiset.
static final SqlTypeTransform	TO_MULTISET_ELEMENT_TYPE	Parameter type-inference transform strategy where a derived type must be a multiset type and the returned type is the multiset's element type.
static final SqlTypeTransform	TO_MULTISET_QUERY	Parameter type-inference transform strategy that wraps a given type in a multiset or wraps a field of the given type in a multiset if the given type is struct with one field.
static final SqlTypeTransform	TO_NOT_NULLABLE	Parameter type-inference transform strategy where a derived type is transformed into the same type but not nullable.
static final SqlTypeTransform	TO_NULLABLE	Parameter type-inference transform strategy where a derived type is transformed into the same type but nullable if any of a calls operands is nullable.
static final SqlTypeTransform	TO_NULLABLE_ALL	Parameter type-inference transform strategy where a derived type is transformed into the same type, but nullable if and only if all of a call's operands are nullable.
static final SqlTypeTransform	TO_VARYING	Type-inference strategy whereby the result type of a call is VARYING the type given.

Constructor Summary

Constructors

Constructor	Description
SqlTypeTransforms()

Method Summary

Methods inherited from class java.lang.Object

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

Field Details

TO_NULLABLE

public static final SqlTypeTransform TO_NULLABLE

Parameter type-inference transform strategy where a derived type is transformed into the same type but nullable if any of a calls operands is nullable.

TO_NULLABLE_ALL

public static final SqlTypeTransform TO_NULLABLE_ALL

Parameter type-inference transform strategy where a derived type is transformed into the same type, but nullable if and only if all of a call's operands are nullable.

TO_NOT_NULLABLE

public static final SqlTypeTransform TO_NOT_NULLABLE

Parameter type-inference transform strategy where a derived type is transformed into the same type but not nullable.

FORCE_NULLABLE

public static final SqlTypeTransform FORCE_NULLABLE

Parameter type-inference transform strategy where a derived type is transformed into the same type with nulls allowed.

LEAST_NULLABLE

public static final SqlTypeTransform LEAST_NULLABLE

Type-inference strategy whereby the result is NOT NULL if any of the arguments is NOT NULL; otherwise the type is unchanged.

TO_VARYING

public static final SqlTypeTransform TO_VARYING

Type-inference strategy whereby the result type of a call is VARYING the type given. The length returned is the same as length of the first argument. Return type will have same nullability as input type nullability. First Arg must be of string type.

TO_MULTISET_ELEMENT_TYPE

public static final SqlTypeTransform TO_MULTISET_ELEMENT_TYPE

Parameter type-inference transform strategy where a derived type must be a multiset type and the returned type is the multiset's element type.

See Also:

• MultisetSqlType.getComponentType()

TO_MULTISET

public static final SqlTypeTransform TO_MULTISET

Parameter type-inference transform strategy that wraps a given type in a multiset.

See Also:

• RelDataTypeFactory.createMultisetType(RelDataType, long)

TO_MULTISET_QUERY

public static final SqlTypeTransform TO_MULTISET_QUERY

Parameter type-inference transform strategy that wraps a given type in a multiset or wraps a field of the given type in a multiset if the given type is struct with one field. It is used when a multiset input is a sub-query.

TO_ARRAY

public static final SqlTypeTransform TO_ARRAY

Parameter type-inference transform strategy that wraps a given type in a array.

See Also:

• RelDataTypeFactory.createArrayType(RelDataType, long)

TO_MEASURE

public static final SqlTypeTransform TO_MEASURE

Parameter type-inference transform that transforms T to MEASURE<T> for some type T.

FROM_MEASURE

public static final SqlTypeTransform FROM_MEASURE

Parameter type-inference transform that transforms MEASURE<T> to T for some type T. Inverse of TO_MEASURE.

TO_ARRAY_QUERY

public static final SqlTypeTransform TO_ARRAY_QUERY

Parameter type-inference transform strategy that wraps a given type in an array or wraps a field of the given type in an array if the given type is struct with one field. It is used when an array input is a sub-query.

TO_MAP

public static final SqlTypeTransform TO_MAP

Parameter type-inference transform strategy that converts a two-field record type to a MAP type.

See Also:

• RelDataTypeFactory.createMapType(org.apache.calcite.rel.type.RelDataType, org.apache.calcite.rel.type.RelDataType)

ONLY_COLUMN

public static final SqlTypeTransform ONLY_COLUMN

Parameter type-inference transform strategy where a derived type must be a struct type with precisely one field and the returned type is the type of that field.

Constructor Details

SqlTypeTransforms

public SqlTypeTransforms()