## 66.7. Examples

The core PostgreSQL distribution includes the GIN operator classes previously shown in Table 66.1. The following `contrib` modules also contain GIN operator classes:

`btree_gin`

  B-tree equivalent functionality for several data types

`hstore`

  Module for storing (key, value) pairs

`intarray`

  Enhanced support for `int[]`

`pg_trgm`

  Text similarity using trigram matching