org.eigenbase.sql.fun
Class SqlAvgAggFunction

java.lang.Object
  org.eigenbase.sql.SqlOperator
      org.eigenbase.sql.SqlFunction
          org.eigenbase.sql.SqlAggFunction
              org.eigenbase.sql.fun.SqlAvgAggFunction

All Implemented Interfaces:

Aggregation

public class SqlAvgAggFunction
extends SqlAggFunction

Avg is an aggregator which returns the average of the values which go into it. It has precisely one argument of numeric type (int, long, float, double), and the result is the same type.

Version:

$Id: //open/dev/farrago/src/org/eigenbase/sql/fun/SqlAvgAggFunction.java#8 $

Author:

jhyde

Field Summary

private RelDataType

type

Fields inherited from class org.eigenbase.sql.SqlOperator

MaxPrec, NL

Constructor Summary

SqlAvgAggFunction(RelDataType type)

Method Summary

RelDataType[]	getParameterTypes(RelDataTypeFactory typeFactory) Returns the parameter types accepted by this Aggregation.
RelDataType	getReturnType(RelDataTypeFactory typeFactory) Returns the type of the result yielded by this Aggregation.
OJClass[]	getStartParameterTypes()
RelDataType	getType()

Methods inherited from class org.eigenbase.sql.SqlAggFunction

isQuantifierAllowed, validateCall

Methods inherited from class org.eigenbase.sql.SqlFunction

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

Methods inherited from class org.eigenbase.sql.SqlOperator

acceptCall, acceptCall, adjustType, argumentMustBeScalar, checkOperandCount, checkOperandTypes, createCall, createCall, createCall, createCall, equals, getAllowedSignatures, getAllowedSignatures, getKind, getLeftPrec, getMonotonicity, getName, getOperandCountRange, getOperandTypeChecker, getOperandTypeInference, getReturnTypeInference, getRightPrec, getSignatureTemplate, hashCode, inferReturnType, inferReturnType, isAggregator, isDeterministic, isDynamicFunction, isName, leftPrec, preValidateCall, requiresDecimalExpansion, rewriteCall, rightPrec, toString, unparseListClause, unparseListClause, validateOperands

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.eigenbase.rel.Aggregation

getName

Field Detail

type

private final RelDataType type

Constructor Detail

SqlAvgAggFunction

public SqlAvgAggFunction(RelDataType type)

Method Detail

getParameterTypes

public RelDataType[] getParameterTypes(RelDataTypeFactory typeFactory)

Description copied from interface: Aggregation

Returns the parameter types accepted by this Aggregation.

Parameters:

typeFactory - Type factory to create the types

Returns:

Array of parameter types

getType

public RelDataType getType()

getReturnType

public RelDataType getReturnType(RelDataTypeFactory typeFactory)

Description copied from interface: Aggregation

Returns the type of the result yielded by this Aggregation.

Parameters:

typeFactory - Type factory to create the type

Returns:

Result type

getStartParameterTypes

public OJClass[] getStartParameterTypes()

Overrides:

getStartParameterTypes in class SqlAggFunction