MySQL

Description

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

• Only the latest feature values are persisted

Getting started

In order to use this online store, you'll need to run pip install 'feast[mysql]'. You can get started by then running feast init and then setting the feature_store.yaml as described below.

Example

feature_store.yaml

project: my_feature_repo
registry: data/registry.db
provider: local
online_store:
    type: mysql
    host: DB_HOST
    port: DB_PORT
    database: DB_NAME
    user: DB_USERNAME
    password: DB_PASSWORD

The full set of configuration options is available in MySQLOnlineStoreConfig.

Batch write mode

By default, the MySQL online store performs row-by-row insert and commit for each feature record. While this ensures per-record atomicity, it can lead to significant overhead on write operations — especially on distributed SQL databases (for example, TiDB, which is MySQL-compatible and uses a consensus protocol).

To improve writing performance, you can enable batch write mode by setting batch_write to true and batch_size, which executes multiple insert queries in batches and commits them together per batch instead of committing each record individually.

feature_store.yaml

project: my_feature_repo
registry: data/registry.db
provider: local
online_store:
    type: mysql
    host: DB_HOST
    port: DB_PORT
    database: DB_NAME
    user: DB_USERNAME
    password: DB_PASSWORD
    batch_write: true
    batch_size: 100

Functionality Matrix

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

	Mys
write feature values to the online store	yes
read feature values from the online store	yes
update infrastructure (e.g. tables) in the online store	yes
teardown infrastructure (e.g. tables) in the online store	yes
generate a plan of infrastructure changes	no
support for on-demand transforms	yes
readable by Python SDK	yes
readable by Java	no
readable by Go	no
support for entityless feature views	yes
support for concurrent writing to the same key	no
support for ttl (time to live) at retrieval	no
support for deleting expired data	no
collocated by feature view	yes
collocated by feature service	no
collocated by entity key	no

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