## 61.5. Examples

The PostgreSQL source distribution includes several examples of index methods implemented using GiST. The core system currently provides text search support (indexing for `tsvector` and `tsquery`) as well as R-Tree equivalent functionality for some of the built-in geometric data types (see `src/backend/access/gist/gistproc.c`). The following `contrib` modules also contain GiST operator classes:

`btree_gist`

  B-tree equivalent functionality for several data types

`cube`

  Indexing for multidimensional cubes

`hstore`

  Module for storing (key, value) pairs

`intarray`

  RD-Tree for one-dimensional array of int4 values

`ltree`

  Indexing for tree-like structures

`pg_trgm`

  Text similarity using trigram matching

`seg`

  Indexing for “float ranges”