# Join tuning options

Use the broadcast join tuning option instead of the hash join to optimize join queries when the size of one side of the data is below a specific threshold. Customizing your broadcast join can efficiently join a large table with small tables, such as a fact table with a dimensions table, which can reduce the amount of data sent over the network.

| Option                      | Description                                                                                                                                                                                                                                     | Value type | Example value |
| --------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ---------- | ------------- |
| **join.broadcast.stepName** | Marks a DataFrame as small enough for use in broadcast joins. See the [Spark API documentation](https://spark.apache.org/docs/2.3.0/api/java/org/apache/spark/sql/functions.html#broadcast-org.apache.spark.sql.Dataset-) for more information. | String     | stepName      |


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