Apache Solr v9 Range Faceting Tutorial

Apache Solr v9 Range Faceting Tutorial

Solr Documentation Link

This tutorial does not cover all Range Facet options. Refer to the document link above for full details. 

This tutorial will cover some of the facet options along with visual examples to help solidify your understanding.

This is the subset of parameters that are explained in this tutorial.

Parameter	Description
field	The numeric field or date field to produce range buckets from.
start	Lower bound of the ranges.
end	Upper bound of the ranges.
gap	Size of each range bucket produced.
include	By default, the ranges used to compute range faceting between start and end are   inclusive of their lower bounds and exclusive of the upper bounds. This default, equivalent to  "lower" below, will not result in double counting at the boundaries. The include parameter  may be any combination of the following options: "lower" all gap based ranges include their lower bound "upper" all gap based ranges include their upper bound "edge" the first and last gap ranges include their edge bounds (i.e., lower for  the first one, upper for the last one) even if the corresponding upper/lower option  is not specified

This tutorial is based on code that uses SolrJ and the RangeFacetMap. Here is an example of code.

RangeFacetMap rangeFacetMap = new RangeFacetMap("BirthYears",

                                                1910,

                                                1950,

                                                3);

//Note: If additional parameters are needed, put them directly into the facet map

//by key according to documentation.

// https://solr.apache.org/guide/solr/latest/query-guide/faceting.html

//

// Example: rangeFacetMap.put("hardened",true)

// Example: rangeFacetMap.put("include",Make.listOf("upper"))

// Example: rangeFacetMap.put("other", "after")

Facet Data

The example data is a birth year field and the count of records that have that birth year. 

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Gap Size 1

RangeFacetMap rangeFacetMap = new RangeFacetMap("BirthYears",

                                                1900,

                                                1907,

                                                1);

Each bucket is represented by a unique color.

Lower

All gap based ranges include their lower bound.

Start = 1900, End = 1907, Gap = 1, include = “lower”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	1
1901	2
1902	3
1903	1
1904	2
1905	3
1906	1

Upper

All gap based ranges include their upper bound.

Start = 1900, End = 1907, Gap = 1, include = “upper”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	2
1901	3
1902	1
1903	2
1904	3
1905	1
1906	2

Edge

The first and last gap ranges include their edge bounds (i.e., lower for the first one, upper for the last one) 

even if the corresponding upper/lower option is not specified.

Start = 1900, End = 1907, Gap = 1, include = “edge”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	1
1901	0
1902	0
1903	0
1904	0
1905	0
1906	2

UPPER and LOWER

Start = 1900, End = 1907, Gap = 1, include = “lower”, “upper”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	3
1901	5
1902	4
1903	3
1904	5
1905	4
1906	3

Gap Size 2

RangeFacetMap rangeFacetMap = new RangeFacetMap("BirthYears",

                                                1900,

                                                1907,

                                                2);

Each bucket is represented by a unique color.

Lower

All gap based ranges include their lower bound.

Start = 1900, End = 1907, Gap = 2, include = “lower”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	3
1902	4
1904	5
1906	3

Upper

All gap based ranges include their upper bound.

Start = 1900, End = 1907, Gap = 2, include = “upper”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	5
1902	3
1904	4
1906	5

Edge

The first and last gap ranges include their edge bounds (i.e., lower for the first one, upper for the last one) 

even if the corresponding upper/lower option is not specified.

Start = 1900, End = 1907, Gap = 2, include = “edge”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	3
1902	1
1904	3
1906	2

UPPER and LOWER

Start = 1900, End = 1907, Gap = 2, include = “lower”, “upper”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	6
1902	6
1904	6
1906	6

Gap Size 3

RangeFacetMap rangeFacetMap = new RangeFacetMap("BirthYears",

                                                1900,

                                                1907,

                                                3);

Each bucket is represented by a unique color.

Lower

All gap based ranges include their lower bound.

Start = 1900, End = 1907, Gap = 3, include = “lower”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	6
1903	6
1906	6

Upper

All gap based ranges include their upper bound.

Start = 1900, End = 1907, Gap = 3, include = “upper”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	6
1903	6
1906	6

Edge

The first and last gap ranges include their edge bounds (i.e., lower for the first one, upper for the last one) 

even if the corresponding upper/lower option is not specified.

Start = 1900, End = 1907, Gap = 3, include = “edge”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	6
1903	5
1906	5

Gap Size 4

RangeFacetMap rangeFacetMap = new RangeFacetMap("BirthYears",

                                                1900,

                                                1907,

                                                4);

Each bucket is represented by a unique color.

Lower

All gap based ranges include their lower bound.

Start = 1900, End = 1907, Gap = 4, include = “lower”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	7
1904	8

Upper

All gap based ranges include their upper bound.

Start = 1900, End = 1907, Gap = 4, include = “upper”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	8
1904	9

Edge

The first and last gap ranges include their edge bounds (i.e., lower for the first one, upper for the last one) 

even if the corresponding upper/lower option is not specified.

Start = 1900, End = 1907, Gap = 4, include = “edge”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	7
1904	6

Gap Size 5

RangeFacetMap rangeFacetMap = new RangeFacetMap("BirthYears",

                                                1900,

                                                1907,

                                                5);

Each bucket is represented by a unique color.

Lower

All gap based ranges include their lower bound.

Start = 1900, End = 1907, Gap = 5, include = “lower”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	9
1905	10

Upper

All gap based ranges include their upper bound.

Start = 1900, End = 1907, Gap = 5, include = “upper”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	11
1905	9

Edge

The first and last gap ranges include their edge bounds (i.e., lower for the first one, upper for the last one) 

even if the corresponding upper/lower option is not specified.

Start = 1900, End = 1907, Gap = 5, include = “edge”

1899	1900	1901	1902	1903	1904	1905	1906	1907	1908	1909	1910	1911	1912	1913
3	1	2	3	1	2	3	1	2	3	1	2	3	1	2

Value	Count
1900	9
1905	7