org.apache.drill.exec.expr.fn

Class FunctionGenerationHelper

java.lang.Object

org.apache.drill.exec.expr.fn.FunctionGenerationHelper

All Implemented Interfaces:

FunctionNames

public class FunctionGenerationHelper
extends Object
implements FunctionNames

Field Summary

Fields inherited from interface org.apache.drill.common.FunctionNames

ADD, AND, COMPARE_TO_NULLS_HIGH, COMPARE_TO_NULLS_LOW, CONCAT, DIVIDE, EQ, GE, GT, IS_FALSE, IS_NOT_FALSE, IS_NOT_NULL, IS_NOT_TRUE, IS_NULL, IS_TRUE, LE, LIKE, LT, MODULO, MULTIPLY, NE, NEGATE, NOT, OR, SIMILAR_TO, SUBTRACT, XOR

Constructor Summary

Constructors

Constructor and Description
FunctionGenerationHelper()

Method Summary

Modifier and Type	Method and Description
static LogicalExpression	getOrderingComparator(boolean null_high, ClassGenerator.HoldingContainer left, ClassGenerator.HoldingContainer right, FunctionLookupContext functionLookupContext) Finds ordering comparator ("compare_to...") FunctionHolderExpression with a specified ordering for NULL (and considering NULLS equal).
static LogicalExpression	getOrderingComparatorNullsHigh(ClassGenerator.HoldingContainer left, ClassGenerator.HoldingContainer right, FunctionLookupContext registry) Finds ordering comparator ("compare_to...") FunctionHolderExpression with a "NULL high" ordering (and considering NULLS equal).

Methods inherited from class java.lang.Object

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

Constructor Detail

FunctionGenerationHelper

public FunctionGenerationHelper()

Method Detail

getOrderingComparator

public static LogicalExpression getOrderingComparator(boolean null_high,
                                                      ClassGenerator.HoldingContainer left,
                                                      ClassGenerator.HoldingContainer right,
                                                      FunctionLookupContext functionLookupContext)

Finds ordering comparator ("compare_to...") FunctionHolderExpression with a specified ordering for NULL (and considering NULLS equal).

Parameters:

null_high - whether NULL should compare as the lowest value (if false) or the highest value (if true)

left - ...

right - ...

functionLookupContext - ...

Returns:

FunctionHolderExpression containing the found function implementation

getOrderingComparatorNullsHigh

public static LogicalExpression getOrderingComparatorNullsHigh(ClassGenerator.HoldingContainer left,
                                                               ClassGenerator.HoldingContainer right,
                                                               FunctionLookupContext registry)

Finds ordering comparator ("compare_to...") FunctionHolderExpression with a "NULL high" ordering (and considering NULLS equal).

Parameters:

left - ...

right - ...

registry - ...

Returns:

FunctionHolderExpression containing the function implementation