I need to create a PostgreSQL Full Text Search index in Python with SQLAlchemy. Here’s what I want in SQL:
CREATE TABLE person ( id INTEGER PRIMARY KEY, name TEXT ); CREATE INDEX person_idx ON person USING GIN (to_tsvector('simple', name));
Now how do I do the second part with SQLAlchemy when using the ORM:
class Person(db.Model): id = db.Column(db.Integer, primary_key=True) name = db.Column(db.String)
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Answer
You could create index using Index
in __table_args__
. Also I use a function to create ts_vector
to make it more tidy and reusable if more than one field is required. Something like below:
from sqlalchemy.dialects import postgresql def create_tsvector(*args): exp = args[0] for e in args[1:]: exp += ' ' + e return func.to_tsvector('english', exp) class Person(db.Model): id = db.Column(db.Integer, primary_key=True) name = db.Column(db.String) __ts_vector__ = create_tsvector( cast(func.coalesce(name, ''), postgresql.TEXT) ) __table_args__ = ( Index( 'idx_person_fts', __ts_vector__, postgresql_using='gin' ) )
Update: A sample query using index (corrected based on comments):
people = Person.query.filter(Person.__ts_vector__.match(expressions, postgresql_regconfig='english')).all()