Package org.apache.flink.table.planner.functions.sql

Class SqlWindowTableFunction

java.lang.Object

org.apache.calcite.sql.SqlOperator

org.apache.calcite.sql.SqlFunction

org.apache.calcite.sql.SqlWindowTableFunction

org.apache.flink.table.planner.functions.sql.SqlWindowTableFunction

All Implemented Interfaces:

org.apache.calcite.sql.SqlTableFunction

Direct Known Subclasses:

SqlCumulateTableFunction, SqlHopTableFunction, SqlSessionTableFunction, SqlTumbleTableFunction

public class SqlWindowTableFunction
extends org.apache.calcite.sql.SqlWindowTableFunction

Base class for a table-valued function that computes windows. Examples include TUMBLE, HOP, CUMULATE and SESSION.

Note: we extend Calcite's SqlWindowTableFunction, to support additional window_time time attribute column which should keep the same type with original time attribute.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected static class	SqlWindowTableFunction.AbstractOperandMetadata	Partial implementation of operand type checker.

Field Summary

Fields

Modifier and Type	Field	Description
static org.apache.calcite.sql.type.SqlReturnTypeInference	ARG0_TABLE_FUNCTION_WINDOWING	Type-inference strategy whereby the row type of a table function call is a ROW, which is combined from the row type of operand #0 (which is a TABLE) and two additional fields.
protected static String	GAP	The gap interval, only used for SESSION window.
protected static String	PARAM_STEP	The slide interval, only used for HOP window.

Fields inherited from class org.apache.calcite.sql.SqlWindowTableFunction

PARAM_DATA, PARAM_KEY, PARAM_OFFSET, PARAM_SIZE, PARAM_SLIDE, PARAM_TIMECOL

Fields inherited from class org.apache.calcite.sql.SqlOperator

kind, MDX_PRECEDENCE, NL

Constructor Summary

Constructors

Constructor	Description
SqlWindowTableFunction(String name, org.apache.calcite.sql.type.SqlOperandMetadata operandMetadata)	Creates a window table function with a given name.

Method Summary

Modifier and Type	Method	Description
boolean	argumentMustBeScalar(int ordinal)
org.apache.calcite.sql.type.SqlOperandMetadata	getOperandTypeChecker()
org.apache.calcite.sql.type.SqlReturnTypeInference	getRowTypeInference()
static org.apache.calcite.rel.type.RelDataType	inferRowType(org.apache.calcite.rel.type.RelDataTypeFactory typeFactory, org.apache.calcite.rel.type.RelDataType inputRowType, org.apache.calcite.rel.type.RelDataType timeAttributeType)
void	validateCall(org.apache.calcite.sql.SqlCall call, org.apache.calcite.sql.validate.SqlValidator validator, org.apache.calcite.sql.validate.SqlValidatorScope scope, org.apache.calcite.sql.validate.SqlValidatorScope operandScope)

Methods inherited from class org.apache.calcite.sql.SqlFunction

deriveType, getFunctionType, getNameAsId, getParamNames, getParamTypes, getSqlIdentifier, getSyntax, isQuantifierAllowed, unparse, validateQuantifier

Methods inherited from class org.apache.calcite.sql.SqlOperator

acceptCall, acceptCall, adjustType, allowsFraming, checkOperandCount, checkOperandTypes, constructArgNameList, constructArgTypeList, constructOperandList, createCall, createCall, createCall, createCall, createCall, createCall, createCall, equals, getAllowedSignatures, getAllowedSignatures, getKind, getLeftPrec, getMonotonicity, getMonotonicity, getName, getOperandCountRange, getOperandTypeInference, getReturnTypeInference, getRightPrec, getSignatureTemplate, getStrongPolicyInference, hashCode, inferReturnType, inferReturnType, isAggregator, isDeterministic, isDynamicFunction, isGroup, isGroupAuxiliary, isName, isSymmetrical, leftPrec, not, preValidateCall, requiresDecimalExpansion, requiresOrder, requiresOver, reverse, rewriteCall, rightPrec, toString, unparseListClause, unparseListClause, validateOperands, validRexOperands

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.calcite.sql.SqlTableFunction

tableCharacteristic

Field Detail

PARAM_STEP

protected static final String PARAM_STEP

The slide interval, only used for HOP window.

See Also:

Constant Field Values

GAP

protected static final String GAP

The gap interval, only used for SESSION window.

See Also:

Constant Field Values

ARG0_TABLE_FUNCTION_WINDOWING

public static final org.apache.calcite.sql.type.SqlReturnTypeInference ARG0_TABLE_FUNCTION_WINDOWING

Type-inference strategy whereby the row type of a table function call is a ROW, which is combined from the row type of operand #0 (which is a TABLE) and two additional fields. The fields are as follows:

1. window_start: TIMESTAMP type to indicate a window's start
2. window_end: TIMESTAMP type to indicate a window's end
3. window_time: TIMESTAMP type with time attribute metadata to indicate a window's time attribute

Constructor Detail

SqlWindowTableFunction

public SqlWindowTableFunction(String name,
                              org.apache.calcite.sql.type.SqlOperandMetadata operandMetadata)

Creates a window table function with a given name.

Method Detail

getOperandTypeChecker

public org.apache.calcite.sql.type.SqlOperandMetadata getOperandTypeChecker()

Overrides:

getOperandTypeChecker in class org.apache.calcite.sql.SqlWindowTableFunction

getRowTypeInference

public org.apache.calcite.sql.type.SqlReturnTypeInference getRowTypeInference()

Specified by:

getRowTypeInference in interface org.apache.calcite.sql.SqlTableFunction

Overrides:

getRowTypeInference in class org.apache.calcite.sql.SqlWindowTableFunction

validateCall

public void validateCall(org.apache.calcite.sql.SqlCall call,
                         org.apache.calcite.sql.validate.SqlValidator validator,
                         org.apache.calcite.sql.validate.SqlValidatorScope scope,
                         org.apache.calcite.sql.validate.SqlValidatorScope operandScope)

Overrides:

validateCall in class org.apache.calcite.sql.SqlFunction

argumentMustBeScalar

public boolean argumentMustBeScalar(int ordinal)

Overrides because the first parameter of table-value function windowing is an explicit TABLE parameter, which is not scalar.

Overrides:

argumentMustBeScalar in class org.apache.calcite.sql.SqlWindowTableFunction

inferRowType

public static org.apache.calcite.rel.type.RelDataType inferRowType(org.apache.calcite.rel.type.RelDataTypeFactory typeFactory,
                                                                   org.apache.calcite.rel.type.RelDataType inputRowType,
                                                                   org.apache.calcite.rel.type.RelDataType timeAttributeType)