Package org.apache.calcite.sql.type

Class InferTypes

java.lang.Object

org.apache.calcite.sql.type.InferTypes

public abstract class InferTypes
extends Object

Strategies for inferring operand types.

See Also:

• SqlOperandTypeInference
• ReturnTypes

Field Summary

Fields

Modifier and Type	Field	Description
static final SqlOperandTypeInference	ANY_NULLABLE	Operand type-inference strategy where an unknown operand type is assumed to be nullable ANY.
static final SqlOperandTypeInference	BOOLEAN	Operand type-inference strategy where an unknown operand type is assumed to be boolean.
static final SqlOperandTypeInference	FIRST_KNOWN	Operand type-inference strategy where an unknown operand type is derived from the first operand with a known type.
static final SqlOperandTypeInference	RETURN_TYPE	Operand type-inference strategy where an unknown operand type is derived from the call's return type.
static final SqlOperandTypeInference	VARCHAR_1024	Operand type-inference strategy where an unknown operand type is assumed to be VARCHAR(1024).

Method Summary

Modifier and Type	Method	Description
static SqlOperandTypeInference	explicit(List<RelDataType> types)	Returns an SqlOperandTypeInference that returns a given list of types.

Methods inherited from class java.lang.Object

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

Field Details

FIRST_KNOWN

public static final SqlOperandTypeInference FIRST_KNOWN

Operand type-inference strategy where an unknown operand type is derived from the first operand with a known type.

RETURN_TYPE

public static final SqlOperandTypeInference RETURN_TYPE

Operand type-inference strategy where an unknown operand type is derived from the call's return type. If the return type is a record, it must have the same number of fields as the number of operands.

BOOLEAN

public static final SqlOperandTypeInference BOOLEAN

Operand type-inference strategy where an unknown operand type is assumed to be boolean.

VARCHAR_1024

public static final SqlOperandTypeInference VARCHAR_1024

Operand type-inference strategy where an unknown operand type is assumed to be VARCHAR(1024). This is not something which should be used in most cases (especially since the precision is arbitrary), but for IS [NOT] NULL, we don't really care about the type at all, so it's reasonable to use something that every other type can be cast to.

ANY_NULLABLE

public static final SqlOperandTypeInference ANY_NULLABLE

Operand type-inference strategy where an unknown operand type is assumed to be nullable ANY.

Method Details

explicit

public static SqlOperandTypeInference explicit(List<RelDataType> types)

Returns an SqlOperandTypeInference that returns a given list of types.