Package se.kuseman.payloadbuilder.api.catalog

Class ScalarFunctionInfo

java.lang.Object

se.kuseman.payloadbuilder.api.catalog.FunctionInfo

se.kuseman.payloadbuilder.api.catalog.ScalarFunctionInfo

public abstract class ScalarFunctionInfo
extends FunctionInfo

Definition of a scalar function

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ScalarFunctionInfo.AggregateMode	Mode of aggregation

Nested classes/interfaces inherited from class se.kuseman.payloadbuilder.api.catalog.FunctionInfo

FunctionInfo.Arity, FunctionInfo.FunctionType

Constructor Summary

Constructors

Constructor	Description
ScalarFunctionInfo(String name, FunctionInfo.FunctionType type)

Method Summary

Modifier and Type	Method	Description
IAggregator	createAggregator(ScalarFunctionInfo.AggregateMode mode, String catalogAlias, List<IExpression> arguments)	Create an aggregator for this function
ValueVector	evalScalar(IExecutionContext context, ScalarFunctionInfo.AggregateMode mode, TupleVector input, String catalogAlias, List<IExpression> arguments)	Evaluate this function in scalar mode with an aggregation mode.
ValueVector	evalScalar(IExecutionContext context, ScalarFunctionInfo.AggregateMode mode, TupleVector input, ValueVector selection, String catalogAlias, List<IExpression> arguments)	Evaluate this function in scalar mode with an aggregation mode with a row selection.
ValueVector	evalScalar(IExecutionContext context, TupleVector input, String catalogAlias, List<IExpression> arguments)	Evaluate this function in scalar mode.
ValueVector	evalScalar(IExecutionContext context, TupleVector input, ValueVector selection, String catalogAlias, List<IExpression> arguments)	Evaluate this expression against input with a row selection.
IExpression	fold(IExecutionContext context, List<IExpression> arguments)	Folds this function and returns a new expression.
ResolvedType	getAggregateType(List<IExpression> arguments)	Data type of this function in aggregate mode.
ResolvedType	getType(List<IExpression> arguments)	Data type of this function
boolean	isConstant(List<? extends IExpression> arguments)	Returns true if this function is contant

Methods inherited from class se.kuseman.payloadbuilder.api.catalog.FunctionInfo

arity, equals, getDescription, getFunctionType, getName, hashCode, requiresNamedArguments, toString

Methods inherited from class java.lang.Object

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

Constructor Details

ScalarFunctionInfo

public ScalarFunctionInfo(String name,
 FunctionInfo.FunctionType type)

Method Details

fold

public IExpression fold(IExecutionContext context,
 List<IExpression> arguments)

Folds this function and returns a new expression. This can be used to return a literal expression if all arguments are constant etc.

Returns:

New expression if one could be created otherwise null

getType

public ResolvedType getType(List<IExpression> arguments)

Data type of this function

Parameters:

arguments - Supplier for arguments data types

getAggregateType

public ResolvedType getAggregateType(List<IExpression> arguments)

Data type of this function in aggregate mode. NOTE! Only applicable if FunctionInfo.FunctionType is FunctionInfo.FunctionType.AGGREGATE or FunctionInfo.FunctionType.SCALAR_AGGREGATE

Parameters:

arguments - Supplier for arguments data types

evalScalar

public ValueVector evalScalar(IExecutionContext context,
 TupleVector input,
 String catalogAlias,
 List<IExpression> arguments)

Evaluate this function in scalar mode.

evalScalar

public ValueVector evalScalar(IExecutionContext context,
 TupleVector input,
 ValueVector selection,
 String catalogAlias,
 List<IExpression> arguments)

Evaluate this expression against input with a row selection.

evalScalar

public ValueVector evalScalar(IExecutionContext context,
 ScalarFunctionInfo.AggregateMode mode,
 TupleVector input,
 String catalogAlias,
 List<IExpression> arguments)

 Evaluate this function in scalar mode with an aggregation mode.
 This is typically an aggregate function that can also act as a scalar function.

 Example function sum

 select sum(DISTINCT col1)                                <--- aggregate function with aggregate mode
 from table
 group by col2

 select collection.map(x -> x.col > 10).sum(DISTINCT)     <--- scalar function with aggregate mode
 from .....
 

evalScalar

public ValueVector evalScalar(IExecutionContext context,
 ScalarFunctionInfo.AggregateMode mode,
 TupleVector input,
 ValueVector selection,
 String catalogAlias,
 List<IExpression> arguments)

 Evaluate this function in scalar mode with an aggregation mode with a row selection.
 This is typically an aggregate function that can also act as a scalar function.

 Example function sum

 select sum(DISTINCT col1)                                <--- aggregate function with aggregate mode
 from table
 group by col2

 select collection.map(x -> x.col > 10).sum(DISTINCT)     <--- scalar function with aggregate mode
 from .....
 

createAggregator

public IAggregator createAggregator(ScalarFunctionInfo.AggregateMode mode,
 String catalogAlias,
 List<IExpression> arguments)

Create an aggregator for this function

isConstant

public boolean isConstant(List<? extends IExpression> arguments)

Returns true if this function is contant