org.apache.calcite.util

Class Sarg<C extends Comparable<C>>

java.lang.Object

org.apache.calcite.util.Sarg<C>

Type Parameters:

C - Value type

All Implemented Interfaces:

Comparable<Sarg<C>>

public class Sarg<C extends Comparable<C>>
extends Object
implements Comparable<Sarg<C>>

Set of values (or ranges) that are the target of a search.

The name is derived from Search argument, an ancient concept in database implementation; see Access Path Selection in a Relational Database Management System — Selinger et al. 1979 or the "morning paper summary.

In RexNode, a Sarg only occur as the right-hand operand in a call to SqlStdOperatorTable.SEARCH, wrapped in a RexLiteral. Lifecycle methods:

• RexUtil.expandSearch(org.apache.calcite.rex.RexBuilder, org.apache.calcite.rex.RexProgram, org.apache.calcite.rex.RexNode) removes calls to SEARCH and the included Sarg, converting them to comparisons;
• RexSimplify converts complex comparisons on the same argument into SEARCH calls with an included Sarg;
• Various RelBuilder methods, including RelBuilder.in(org.apache.calcite.rex.RexNode, org.apache.calcite.rex.RexNode...) and RelBuilder.between(org.apache.calcite.rex.RexNode, org.apache.calcite.rex.RexNode, org.apache.calcite.rex.RexNode) call RexBuilder methods RexBuilder.makeIn(org.apache.calcite.rex.RexNode, java.util.List<? extends org.apache.calcite.rex.RexNode>) and RexBuilder.makeBetween(org.apache.calcite.rex.RexNode, org.apache.calcite.rex.RexNode, org.apache.calcite.rex.RexNode) that create Sarg instances directly;
• SqlImplementor converts RexCalls to SEARCH into SqlNode AST expressions such as comparisons, BETWEEN and IN.

See Also:

SqlStdOperatorTable.SEARCH

Field Summary

Fields

Modifier and Type	Field and Description
boolean	containsNull
int	pointCount
com.google.common.collect.RangeSet<C>	rangeSet

Method Summary

Modifier and Type	Method and Description
int	compareTo(Sarg<C> o)
boolean	equals(Object o)
int	hashCode()
boolean	isComplementedPoints() Returns whether this Sarg, when negated, is a collection of 1 or more points (and perhaps an IS NULL if containsNull).
boolean	isPoints() Returns whether this Sarg is a collection of 1 or more points (and perhaps an IS NULL if containsNull).
static <C extends Comparable<C>> Sarg<C>	of(boolean containsNull, com.google.common.collect.RangeSet<C> rangeSet) Creates a search argument.
StringBuilder	printTo(StringBuilder sb, BiConsumer<StringBuilder,C> valuePrinter) Prints this Sarg to a StringBuilder, using the given printer to deal with each embedded value.
String	toString() Produces a similar result to RangeSet, but adds ", null" if nulls are matched, and simplifies point ranges.

Methods inherited from class java.lang.Object

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

Field Detail

rangeSet

public final com.google.common.collect.RangeSet<C extends Comparable<C>> rangeSet

containsNull

public final boolean containsNull

pointCount

public final int pointCount

Method Detail

of

public static <C extends Comparable<C>> Sarg<C> of(boolean containsNull,
                                                   com.google.common.collect.RangeSet<C> rangeSet)

Creates a search argument.

toString

public String toString()

Produces a similar result to RangeSet, but adds ", null" if nulls are matched, and simplifies point ranges. For example, the Sarg that allows the range set

[[7‥7], [9‥9], (10‥+∞)]

and also null is printed as

Sarg[7, 9, (10‥+∞), null]

Overrides:

toString in class Object

printTo

public StringBuilder printTo(StringBuilder sb,
                             BiConsumer<StringBuilder,C> valuePrinter)

Prints this Sarg to a StringBuilder, using the given printer to deal with each embedded value.

compareTo

public int compareTo(Sarg<C> o)

Specified by:

compareTo in interface Comparable<Sarg<C extends Comparable<C>>>

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

isPoints

public boolean isPoints()

Returns whether this Sarg is a collection of 1 or more points (and perhaps an IS NULL if containsNull).

Such sargs could be translated as ref = value or ref IN (value1, ...).

isComplementedPoints

public boolean isComplementedPoints()

Returns whether this Sarg, when negated, is a collection of 1 or more points (and perhaps an IS NULL if containsNull).

Such sargs could be translated as ref <> value or ref NOT IN (value1, ...).