Package org.apache.calcite.sql.type

Class OperandHandlers

java.lang.Object

org.apache.calcite.sql.type.OperandHandlers

public abstract class OperandHandlers
extends Object

Strategies for handling operands.

This class defines singleton instances of strategy objects for operand expansion. OperandTypes, ReturnTypes and InferTypes provide similar strategies for operand type checking and inference, and operator return type inference.

See Also:

• SqlOperandTypeChecker
• ReturnTypes
• InferTypes

Field Summary

Fields

Modifier and Type	Field	Description
static final SqlOperandHandler	DEFAULT	The default operand handler visits all operands.
static final SqlOperandHandler	OPERAND_1_MIGHT_BE_TIME_FRAME	An operand handler that tries to convert operand #1 (0-based) into a time frame.

Constructor Summary

Constructors

Constructor	Description
OperandHandlers()

Method Summary

Modifier and Type	Method	Description
static SqlOperandHandler	of(BiFunction<SqlValidator,SqlCall,SqlCall> fn)	Creates an operand handler that applies a function to a call.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT

public static final SqlOperandHandler DEFAULT

The default operand handler visits all operands.

OPERAND_1_MIGHT_BE_TIME_FRAME

public static final SqlOperandHandler OPERAND_1_MIGHT_BE_TIME_FRAME

An operand handler that tries to convert operand #1 (0-based) into a time frame.

For example, the DATE_TRUNC function uses this; the calls DATE_TRUNC('month', orders.order_date), DATE_TRUNC(orders.order_date, MONTH), DATE_TRUNC(orders.order_date, MINUTE15) are all valid. The last uses a user-defined time frame, which appears to the validator as a SqlIdentifier and is then converted to a SqlIntervalQualifier when it matches a defined time frame.

Constructor Details

OperandHandlers

public OperandHandlers()

Method Details

of

public static SqlOperandHandler of(BiFunction<SqlValidator,SqlCall,SqlCall> fn)

Creates an operand handler that applies a function to a call.