> ## Documentation Index
> Fetch the complete documentation index at: https://developers.stellar.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Backfill

> Once your scheduling and orchestration are set up, you might encounter the following scenarios.

Once your scheduling and orchestration are set up, you might encounter the following scenarios:

| Use Case | Description | Solution |
| - | - | - |
| Initial Backfill | You have just setup hubble and would like to ingest historical data | - Option 1. [Data Import](https://developers.stellar.org/docs/data/analytics/hubble/developer-guide/backfill/data-import.md)  **Pros:** Cheap and fast - Option 2: Re-trigger DAGs for past dates  **Cons:** Slow and expensive |
| Bug Fix | You resolved a bug and need to re-ingest a specific data column/s or back fix a data column | - Option 1. [JS UDF](https://developers.stellar.org/docs/data/analytics/hubble/developer-guide/backfill/JS-UDF.md)  **Pros:** Cheap and fast  **Cons:** May need optimized query writing and running in batches  - Option 2: Re-trigger DAGs for past dates  **Cons:** Slow and expensive |
| New data column extraction | You added a new data column/s as part of a feature request and need to backfill data for the newly added column/s | - Option 1. [JS UDF](https://developers.stellar.org/docs/data/analytics/hubble/developer-guide/backfill/JS-UDF.md)  **Pros:** Cheap and fast  **Cons:** May need optimized query writing and running in batches  - Option 2: Re-trigger DAGs for past dates  **Cons:** Slow and expensive |

> [card] [Backfill using JS UDF](https://developers.stellar.org/docs/data/analytics/hubble/developer-guide/backfill/JS-UDF.md)
>
> This document outlines methods to extract required fields from the XDR of raw data.

> [card] [Data Import](https://developers.stellar.org/docs/data/analytics/hubble/developer-guide/backfill/data-import.md)
>
> This document outlines methods to perform inital backfill when setting up hubble.