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
RexUnknownAs	nullAs
int	pointCount
com.google.common.collect.RangeSet<C>	rangeSet

Method Summary

Modifier and Type	Method and Description
int	compareTo(Sarg<C> o)
int	complexity() Returns a measure of the complexity of this expression.
boolean	equals(@Nullable Object o)
int	hashCode()
boolean	isAll() Returns whether this Sarg includes all values (including or not including null).
boolean	isComplementedPoints() Returns whether this Sarg, when negated, is a collection of 1 or more points (and perhaps an IS NULL if nullAs == RexUnknownAs.TRUE).
boolean	isNone() Returns whether this Sarg includes no values (including or not including null).
boolean	isPoints() Returns whether this Sarg is a collection of 1 or more points (and perhaps an IS NULL if nullAs == RexUnknownAs.TRUE).
Sarg	negate() Returns a Sarg that matches a value if and only this Sarg does not.
static <C extends Comparable<C>> Sarg<C>	of(boolean containsNull, com.google.common.collect.RangeSet<C> rangeSet) Deprecated.
static <C extends Comparable<C>> Sarg<C>	of(RexUnknownAs nullAs, 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()

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

nullAs

public final RexUnknownAs nullAs

pointCount

public final int pointCount

Method Detail

of

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

Deprecated.

of

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

Creates a search argument.

toString

public String toString()

Produces a similar result to RangeSet, but adds "; NULL AS FALSE" or "; NULL AS TRUE" to indicate nullAs, 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 AS TRUE]

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(@Nullable Object o)

Overrides:

equals in class Object

isAll

public boolean isAll()

Returns whether this Sarg includes all values (including or not including null).

isNone

public boolean isNone()

Returns whether this Sarg includes no values (including or not including null).

isPoints

public boolean isPoints()

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

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 nullAs == RexUnknownAs.TRUE).

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

complexity

public int complexity()

Returns a measure of the complexity of this expression.

It is basically the number of values that need to be checked against (including NULL).

Examples:

• x = 1, x <> 1, x > 1 have complexity 1
• x > 1 or x is null has complexity 2
• x in (2, 4, 6) or x > 20 has complexity 4
• x between 3 and 8 or x between 10 and 20 has complexity 2

negate

public Sarg negate()

Returns a Sarg that matches a value if and only this Sarg does not.