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

# FAQ

> Common questions and troubleshooting for the ADLS + Databricks connector.

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## Connector Lifecycle

<AccordionGroup>
  <Accordion title="What happens if I delete a connector?">
    Deleting a source triggers an approval workflow based on your organization's settings. Once approved, the source and all associated metadata are permanently deleted. The deletion cannot be undone after approval.
  </Accordion>

  <Accordion title="What happens to existing data and alerts if a connector is paused or disconnected?">
    Existing metadata, quality scores, and alerts are retained while the connector is inactive. No new data is collected until the connector is re-enabled.
  </Accordion>

  <Accordion title="How long does Prizm retain historical data?">
    The default data retention window for time-series observability data and quality score history is **90 days**.
  </Accordion>
</AccordionGroup>

## Setup & Configuration

<AccordionGroup>
  <Accordion title="My cluster does not appear in the dropdown.">
    Only clusters that are currently running or resizing are listed. Start your cluster, then refresh the dropdown.
  </Accordion>

  <Accordion title="No containers appear when I configure my source.">
    Your ADLS credentials are missing list permission on the storage account. Confirm the identity has Storage Blob Data Reader (source container) or Storage Blob Data Contributor (managed-storage container) as appropriate.
  </Accordion>

  <Accordion title="I selected a container and it disappeared from my selection.">
    Your credentials don't have read access to that specific container. The dropdown lists every container in the account because Prizm can't filter it to read-access-only containers for a service principal or access token — but Prizm still checks read access on selection. If it fails, a toast appears and the container is auto-removed. Choose a container your credentials can read, or ask your Azure administrator to grant access.
  </Accordion>

  <Accordion title="Can I use Amazon EMR or Cloudera instead of Databricks?">
    Not at this time. Databricks is the only supported external Spark engine today.
  </Accordion>

  <Accordion title="What if my Databricks environment cannot reach ADLS?">
    This is handled through agent-outbound connectivity rather than manual firewall rules. Confirm agent-outbound is correctly configured and reachable for your environment. If jobs still fail to reach ADLS, contact your Prizm account team.
  </Accordion>
</AccordionGroup>

## Authentication & Permissions

<AccordionGroup>
  <Accordion title="My jobs started failing after working correctly for weeks.">
    If you're using a Service Principal, check whether the Azure client secret has expired — an expired secret prevents Prizm from reading ADLS. If you're using Managed Identity, there's no secret to expire — check instead whether the role assignments on the Access Connector are still in place.
  </Accordion>

  <Accordion title="My storage credential shows as unavailable, or an external location test fails.">
    Confirm the Access Connector (or service principal) has been granted the correct role on the correct container — Storage Blob Data Reader on the source container, Storage Blob Data Contributor on the managed-storage container — and that role propagation has completed. This can take a few minutes.
  </Accordion>

  <Accordion title="Reads work but writes to the managed-storage container fail.">
    This almost always means the identity has Storage Blob Data Reader instead of Storage Blob Data Contributor on the write container, or is missing Storage Blob Delegator at the storage-account level. Confirm both are assigned.
  </Accordion>

  <Accordion title="Credential vending fails, or Unity Catalog cannot issue a SAS token for the external location.">
    Storage Blob Delegator must be assigned at the **storage-account** scope, not the container scope — a container-scoped assignment will not enable delegation-key issuance. Re-check the scope of the role assignment, not just its presence.
  </Accordion>

  <Accordion title="Trino cannot see the Iceberg table.">
    Confirm external data access is enabled at the metastore level and the Trino principal has `EXTERNAL USE SCHEMA` on the schema — table-level grants alone are not sufficient for external engine access.
  </Accordion>
</AccordionGroup>

***

<CardGroup cols={2}>
  <Card title="Troubleshooting" icon="wrench" href="/help/troubleshooting">
    For connection errors, permission issues, and performance problems.
  </Card>

  <Card title="Glossary" icon="circle-question" href="/help/glossary">
    For definitions of terms used in this FAQ.
  </Card>
</CardGroup>