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Diffstat (limited to 'docs/ref/contrib/postgres/lookups.txt')
| -rw-r--r-- | docs/ref/contrib/postgres/lookups.txt | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/docs/ref/contrib/postgres/lookups.txt b/docs/ref/contrib/postgres/lookups.txt index 1f0af07b0d..daf784e221 100644 --- a/docs/ref/contrib/postgres/lookups.txt +++ b/docs/ref/contrib/postgres/lookups.txt @@ -2,6 +2,32 @@ PostgreSQL specific lookups =========================== +Trigram similarity +================== + +.. fieldlookup:: trigram_similar + +.. versionadded:: 1.10 + +The ``trigram_similar`` lookup allows you to perform trigram lookups, +measuring the number of trigrams (three consecutive characters) shared, using a +dedicated PostgreSQL extension. A trigram lookup is given an expression and +returns results that have a similarity measurement greater than the current +similarity threshold. + +To use it, add ``'django.contrib.postgres'`` in your :setting:`INSTALLED_APPS` +and activate the `pg_trgm extension +<http://www.postgresql.org/docs/current/interactive/pgtrgm.html>`_ on +PostgreSQL. You can install the extension using the +:class:`~django.contrib.postgres.operations.TrigramExtension` migration +operation. + +The ``trigram_similar`` lookup can be used on +:class:`~django.db.models.CharField` and :class:`~django.db.models.TextField`:: + + >>> City.objects.filter(name__trigram_similar="Middlesborough") + ['<City: Middlesbrough>'] + ``Unaccent`` ============ |