# Use Hudi metadata for improved performance
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The Apache Hudi has a [metadata table](https://hudi.apache.org/docs/next/metadata/) that contains indexing features for improved performance like file listing, data skipping using column statistics, and a bloom filter based index.

Of these features, Athena currently supports only the file listing index. The file listing index eliminates file system calls like "list files" by fetching the information from an index which maintains a partition to files mapping. This removes the need to recursively list each and every partition under the table path to get a view of the file system. When you work with large datasets, this indexing drastically reduces the latency that would otherwise occur when getting the list of files during writes and queries. It also avoids bottlenecks like request limits throttling on Amazon S3 `LIST` calls.

**Note**  
Athena does not support data skipping or bloom filter indexing at this time.

## Enabling the Hudi metadata table
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Metadata table based file listing is disabled by default. To enable the Hudi metadata table and the related file listing functionality, set the `hudi.metadata-listing-enabled` table property to `TRUE`.

**Example**  
The following `ALTER TABLE SET TBLPROPERTIES` example enables the metadata table on the example `partition_cow` table.

```
ALTER TABLE partition_cow SET TBLPROPERTIES('hudi.metadata-listing-enabled'='TRUE')
```

## Use bootstrap generated metadata
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Starting in Apache Hudi version 0.6.0, the bootstrap operation feature provides better performance with existing Parquet datasets. Instead of rewriting the dataset, a bootstrap operation can generate metadata only, leaving the dataset in place. 

You can use Athena to query tables from a bootstrap operation just like other tables based on data in Amazon S3. In your `CREATE TABLE` statement, specify the Hudi table path in your `LOCATION` clause. 

For more information about creating Hudi tables using the bootstrap operation in Amazon EMR, see the article [New features from Apache Hudi available in Amazon EMR](https://aws.amazon.com/blogs/big-data/new-features-from-apache-hudi-available-in-amazon-emr/) in the AWS Big Data Blog.