TSVector¶

`TSVectorField`¶

class TSVectorField(fields, dictionary)¶

TSVectorField.fields¶

A tuple containing a tuple of fields and rank to be indexed, it can be only the field name the default the rank ‘D’ will be added

Example:

('field_name', ('field_name2', 'A'))

Will result in:

(('field_name', 'D'), ('field_name2', 'A'))

TSVectorField.dictionary¶

Can be string with the dictionary name pg_catalog.pg_ts_config consult PostgreSQL documentation 12.6. Dictionaries
A CharField with choices in case of multiple dictionaries.

Caution

Dictionary(ies) used must be installed in your database, check pg_catalog.pg_ts_config

Will raise exception exceptions.FieldError if lookup isn’t tsquery, search or isearch or not a valid option dictionary (in case of multiple dictionaries)

Caution

TSVectorField does not support iexact, it will raise an exception

`FTSLookups`¶

search¶

Only return results that match all the lexemes.

isearch¶

Return results if match any of the lexemes.

tsquery¶

Raw tsquery, for full control over PostgreSQL to_tsquery. Check PostgreSQL documentation pg_docs12.3.2. Parsing Queries <textsearch-controls.html#TEXTSEARCH-PARSING-QUERIES

Single dictionary examples¶

class Article(models.Model):
    title = models.CharField(max_length=255)
    article = models.TextField()
    fts = TSVectorField(
        (('title', 'A'), 'article'),
        dictionary='portuguese'
    )

    def __str__(self):
        return self.title

>>> Article.objects.bulk_create([
    Article(title='Python', article='The python programing language')
    Article(title='Monty Python', article='British surreal comedy group')
    Article(title="Monty Python's Flying Circus", article="Monty Python's Flying Circus was a series created by Monty Python comedy group")
])

Using search for python programing and python comedy:

>>> Article.objects.filter(fts__search='python programing')
[<Article: Python>]
>>> Article.objects.filter(fts__search='comedy group')
[<Article: Monty Python's Flying Circus>, <Article: Monty Python>]
>>> Article.objects.filter(fts__search='PHP')
[]

If you use isearch will search for any of the lexemes:

>>> Article.objects.filter(fts__isearch='python programing')
[<Article: Python>, <Article: Monty Python's Flying Circus>, <Article: Monty Python>]
>>> Article.objects.filter(fts__isearch='PHP')
[]

`DictionaryTransform`¶

Preforms a transformation for dictionary for searching with portuguese lexemes fts__portuguese__search

It checks if the dictionary is in options, only works with multiple dictionaries.

Multiple dictionaries examples¶

class Article(models.Model):
    title = models.CharField(max_length=255)
    article = models.TextField()

    dicts = models.CharField(  # the dictionary field
        max_length=15,
        choices=(('english', 'english'), ('portuguese', 'portuguese')),
        default='english',
        db_index=True
    )

    fts = TSVectorField(
        (('title', 'A'), 'article'),
        dictionary='dicts'  # refers to the dictionary field
    )

    def __str__(self):
        return '%s in %s' % (self.title, self.language)

>>> Article.objects.bulk_create([
    Article(title='Python', article='The python programing language', language='english')
    Article(title='Monty Python', article='British surreal comedy group', language='english')
    Article(title="Monty Python's Flying Circus", article="Monty Python's Flying Circus was a series created by Monty Python comedy group", language='english')
    Article(title='Python', article='A linguagem de programação python', language='portuguese')
    Article(title='Monty Python', article='Um grupo de comédia britânico', language='portuguese')
    Article(title="Os Malucos do Circo", article="Os Malucos do Circo ou Monty Python's Flying Circus no titulo orignial foi criada pelo grupo de comédia Monty Python", language='portuguese')
])

Use the dictionary transform, also we should filter by the dictionary used:

>>> Article.objects.filter(fts__english__search='python programing', dicts='english')
[<Article: Python in english>]
>>> Article.objects.filter(fts__english__search='monty python', dicts='portuguese')
[<Article: Monty Python in portuguese>, <Article: Os Malucos do Circo in portuguese>]

Note

Not filtering the results by it’s dictionary is possible, but results won’t be reliable:

>>> Article.objects.filter(fts__english__search='python programing')
[<Article: Python in english>]  # nothing strange
>>> Article.objects.filter(fts__portuguese__search='python programing')
[]  # no results

Note

The DictionaryTransform only accepts dictionaries that are defined in options.