org.apache.hadoop.hive.ql.parse.type

Interface FunctionHelper

All Known Implementing Classes:

HiveFunctionHelper

public interface FunctionHelper

Interface to handle function information while generating Calcite RexNode.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	FunctionHelper.AggregateInfo Class to store aggregate function related information.
static class	FunctionHelper.FieldCollation

Method Summary

Modifier and Type	Method and Description
List<org.apache.calcite.rex.RexNode>	convertInputs(FunctionInfo functionInfo, List<org.apache.calcite.rex.RexNode> inputs, org.apache.calcite.rel.type.RelDataType returnType) Given function information, the inputs to that function, and the expected return type, it will return the list of inputs with any necessary adjustments, e.g., casting of expressions.
default org.apache.calcite.rex.RexNode	foldExpression(org.apache.calcite.rex.RexNode expr) Folds expression according to function semantics.
FunctionHelper.AggregateInfo	getAggregateFunctionInfo(boolean isDistinct, boolean isAllColumns, String aggregateName, List<org.apache.calcite.rex.RexNode> aggregateParameters, List<FunctionHelper.FieldCollation> fieldCollations) Returns aggregation information based on given parameters.
org.apache.calcite.rex.RexNode	getExpression(String functionText, FunctionInfo functionInfo, List<org.apache.calcite.rex.RexNode> inputs, org.apache.calcite.rel.type.RelDataType returnType) Given function information and text, inputs to a function, and the expected return type, it will return an expression node containing the function call.
FunctionInfo	getFunctionInfo(String functionText) Returns function information based on function text.
org.apache.calcite.rel.type.RelDataType	getReturnType(FunctionInfo functionInfo, List<org.apache.calcite.rex.RexNode> inputs) Given function information and its inputs, it returns the type of the output of the function.
FunctionHelper.AggregateInfo	getWindowAggregateFunctionInfo(boolean isDistinct, boolean isAllColumns, String aggregateName, List<org.apache.calcite.rex.RexNode> aggregateParameters) Returns aggregation information for analytical function based on given parameters.
boolean	isAndFunction(FunctionInfo fi) returns true if FunctionInfo is an And function.
boolean	isCompareFunction(FunctionInfo fi) returns true if FunctionInfo is a compare function (e.g.
boolean	isConsistentWithinQuery(FunctionInfo fi) Returns whether the expression, for a single query, returns the same result given the same arguments/children.
boolean	isEqualFunction(FunctionInfo fi) returns true if FunctionInfo is an == function.
boolean	isInFunction(FunctionInfo fi) returns true if FunctionInfo is an In function.
boolean	isNSCompareFunction(FunctionInfo fi)
boolean	isOrFunction(FunctionInfo fi) returns true if FunctionInfo is an Or function.
boolean	isStateful(FunctionInfo fi) returns true if FunctionInfo is a stateful function.

Method Detail

getFunctionInfo

FunctionInfo getFunctionInfo(String functionText)
                      throws SemanticException

Returns function information based on function text.

Throws:

SemanticException

getReturnType

org.apache.calcite.rel.type.RelDataType getReturnType(FunctionInfo functionInfo,
                                                      List<org.apache.calcite.rex.RexNode> inputs)
                                               throws SemanticException

Given function information and its inputs, it returns the type of the output of the function.

Throws:

SemanticException

convertInputs

List<org.apache.calcite.rex.RexNode> convertInputs(FunctionInfo functionInfo,
                                                   List<org.apache.calcite.rex.RexNode> inputs,
                                                   org.apache.calcite.rel.type.RelDataType returnType)
                                            throws SemanticException

Given function information, the inputs to that function, and the expected return type, it will return the list of inputs with any necessary adjustments, e.g., casting of expressions.

Throws:

SemanticException

getExpression

org.apache.calcite.rex.RexNode getExpression(String functionText,
                                             FunctionInfo functionInfo,
                                             List<org.apache.calcite.rex.RexNode> inputs,
                                             org.apache.calcite.rel.type.RelDataType returnType)
                                      throws SemanticException

Given function information and text, inputs to a function, and the expected return type, it will return an expression node containing the function call.

Throws:

SemanticException

getAggregateFunctionInfo

FunctionHelper.AggregateInfo getAggregateFunctionInfo(boolean isDistinct,
                                                      boolean isAllColumns,
                                                      String aggregateName,
                                                      List<org.apache.calcite.rex.RexNode> aggregateParameters,
                                                      List<FunctionHelper.FieldCollation> fieldCollations)
                                               throws SemanticException

Returns aggregation information based on given parameters.

Throws:

SemanticException

getWindowAggregateFunctionInfo

FunctionHelper.AggregateInfo getWindowAggregateFunctionInfo(boolean isDistinct,
                                                            boolean isAllColumns,
                                                            String aggregateName,
                                                            List<org.apache.calcite.rex.RexNode> aggregateParameters)
                                                     throws SemanticException

Returns aggregation information for analytical function based on given parameters.

Throws:

SemanticException

foldExpression

default org.apache.calcite.rex.RexNode foldExpression(org.apache.calcite.rex.RexNode expr)

Folds expression according to function semantics.

isAndFunction

boolean isAndFunction(FunctionInfo fi)

returns true if FunctionInfo is an And function.

isOrFunction

boolean isOrFunction(FunctionInfo fi)

returns true if FunctionInfo is an Or function.

isInFunction

boolean isInFunction(FunctionInfo fi)

returns true if FunctionInfo is an In function.

isCompareFunction

boolean isCompareFunction(FunctionInfo fi)

returns true if FunctionInfo is a compare function (e.g. '<=')

isEqualFunction

boolean isEqualFunction(FunctionInfo fi)

returns true if FunctionInfo is an == function.

isNSCompareFunction

boolean isNSCompareFunction(FunctionInfo fi)

isConsistentWithinQuery

boolean isConsistentWithinQuery(FunctionInfo fi)

Returns whether the expression, for a single query, returns the same result given the same arguments/children. This includes deterministic functions as well as runtime constants (which may not be deterministic across queries).

isStateful

boolean isStateful(FunctionInfo fi)

returns true if FunctionInfo is a stateful function.