Mastering PostgreSQL 11 - Second Edition

Extending BRIN indexes

BRIN supports the same strategies as a btree and therefore needs the same set of operators. The code can be reused nicely:

Operation	Strategy number
Less than	1
Less than or equal	2
Equal	3
Greater than or equal	4
Greater than	5

The support functions required by BRIN are as follows:

Function	Description	Support function number
opcInfo	Provides internal information about the indexed columns	1
add_value	Adds an entry to an existing summary tuple	2
consistent	Checks whether a value matches a condition	3
union	Calculates the union of two summary entries (minimum/maximum values)	4