64.5. 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 "