Please see for an explanation of online stores.

Functionality

Here are the methods exposed by the OnlineStore interface, along with the core functionality supported by the method:

• online_write_batch: write feature values to the online store

• online_read: read feature values from the online store

• update: update infrastructure (e.g. tables) in the online store

• teardown: teardown infrastructure (e.g. tables) in the online store

• plan: generate a plan of infrastructure changes based on feature repo changes

There is also additional functionality not properly captured by these interface methods:

• support for on-demand transforms

• readable by Python SDK

• readable by Java

Finally, there are multiple data models for storing the features in the online store. For example, features could be:

• collocated by feature view

• collocated by feature service

• collocated by entity key

See this for a discussion around the tradeoffs of each of these data models.

There are currently five core online store implementations: SqliteOnlineStore, RedisOnlineStore, DynamoDBOnlineStore, SnowflakeOnlineStore, and DatastoreOnlineStore. There are several additional implementations contributed by the Feast community (PostgreSQLOnlineStore, HbaseOnlineStore, and CassandraOnlineStore), which are not guaranteed to be stable or to match the functionality of the core implementations. Details for each specific online store, such as how to configure it in a feature_store.yaml, can be found .

Below is a matrix indicating which online stores support what functionality.

Description

The Redis online store provides support for materializing feature values into Redis.

• Both Redis and Redis Cluster are supported.

• The data model used to store feature values in Redis is described in more detail here.

Getting started

In order to use this online store, you'll need to install the redis extra (along with the dependency needed for the offline store of choice). E.g.

• pip install 'feast[gcp, redis]'

• pip install 'feast[snowflake, redis]'

• pip install 'feast[aws, redis]'

You can get started by using any of the other templates (e.g. feast init -t gcp or feast init -t snowflake or feast init -t aws), and then swapping in Redis as the online store as seen below in the examples.

Connecting to a single Redis instance:

Connecting to a Redis Cluster with SSL enabled and password authentication:

The full set of configuration options is available in .

The set of functionality supported by online stores is described in detail . Below is a matrix indicating which functionality is supported by the Redis online store.

To compare this set of functionality against other online stores, please see the full .

The online store provides support for materializing feature values into a Snowflake Transient Table for serving online features.

• Only the latest feature values are persisted

The data model for using a Snowflake Transient Table as an online store follows a tall format (one row per feature)):

The online store provides support for materializing feature values into Cloud Datastore. The data model used to store feature values in Datastore is described in more detail .

In order to use this online store, you'll need to run pip install 'feast[gcp]'. You can then get started with the command feast init REPO_NAME -t gcp.

The full set of configuration options is available in .

The set of functionality supported by online stores is described in detail . Below is a matrix indicating which functionality is supported by the Datastore online store.

The online store provides support for materializing feature values into an SQLite database for serving online features.

• All feature values are stored in an on-disk SQLite database

• Only the latest feature values are persisted

The full set of configuration options is available in .

Description

The PostgreSQL online store provides support for materializing feature values into a PostgreSQL database for serving online features.

• Only the latest feature values are persisted

• sslmode, sslkey_path, sslcert_path, and sslrootcert_path are optional

Getting started

In order to use this online store, you'll need to run pip install 'feast[postgres]'. You can get started by then running feast init -t postgres.

The full set of configuration options is available in .

The set of functionality supported by online stores is described in detail . Below is a matrix indicating which functionality is supported by the Postgres online store.

To compare this set of functionality against other online stores, please see the full .

The [Cassandra / Astra DB] online store provides support for materializing feature values into an Apache Cassandra / Astra DB database for online features.

• The whole project is contained within a Cassandra keyspace

• Each feature view is mapped one-to-one to a specific Cassandra table

Description

The DynamoDB online store provides support for materializing feature values into AWS DynamoDB.

Getting started

In order to use this online store, you'll need to run pip install 'feast[aws]'. You can then get started with the command feast init REPO_NAME -t aws.

Example

project: my_feature_repo
registry: data/registry.db
provider: aws
online_store:
  type: dynamodb
  region: us-west-2

The full set of configuration options is available in DynamoDBOnlineStoreConfig.

Permissions

Feast requires the following permissions in order to execute commands for DynamoDB online store:

The following inline policy can be used to grant Feast the necessary permissions:

Lastly, this IAM role needs to be associated with the desired Redshift cluster. Please follow the official AWS guide for the necessary steps .

The set of functionality supported by online stores is described in detail . Below is a matrix indicating which functionality is supported by the DynamoDB online store.

To compare this set of functionality against other online stores, please see the full .