pg_trgm

A contrib module for determining the similarity of text based on trigram matching

pg_trgm is a contrib module providing functions and operators for determining the similarity of alphanumeric text based on trigram matching, and index operator classes for fast string searching.

pg_trgm was added in PostgreSQL 8.0.

Change history

PostgreSQL 14
- GiST/GIN pg_trgm indexes can perform equality lookups (commit 935f6666)
PostgreSQL 13
- marked as a trusted extension (commit eb67623c)
PostgreSQL 11 (extension version 1.4)
- function strict_word_similarity() added (commit be8a7a68)
PostgreSQL 9.6 (extension version 1.3)
- function cleanup and parallel query support (commit 749a787c)
PostgreSQL 9.6 (extension version 1.2)
- support for the triconsistent function for pg_trgm GIN opclass (commit 97f30146)
- performance of similarity searches in GIN indexes improved (commit 25bfa7ef)
PostgreSQL 9.4
- improved heuristics for regular expression index searches (commit 80a5cf64)
PostgreSQL 9.3 (extension version 1.1)
- support indexing of regular-expression searches (commit 3ccae48f)
PostgreSQL 9.1 (extension version 1.0)
- support for LIKE/ILIKE searches added (commit 6e2f3ae8)
- conversion to an extension (commit 629b3af2)
PostgreSQL 8.4
- support for multibyte encoding added (commit b87b52bf)
PostgreSQL 8.3
- GIN index support added (commit 15f91f27)
PostgreSQL 8.0
- added (commit cbfa4092)

Note: some modifications prior to PostgreSQL 9.1 may not be recorded here.

References

PostgreSQL documentation: pg_trgm

Useful links

Postgres text search: balancing query time and relevancy - October 2021 blog article by Stephen Gutekanst / Sourcegraph
Fuzzy string matching with Trigram and Trigraphs - undated article from Postgres OnLine Journal

Version charts

Useful overviews

Useful links

Contents

pg_trgm

Change history

References

Useful links

Categories

See also