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

# FAQ

> Common questions about how Isofold works, integrates, and saves you money.

## Frequently Asked Questions

***

### Will Isofold break my queries?

No. Isofold is designed to preserve semantics and results.

* All rewrites are semantically equivalent
* You can enable verification mode to run both the original and rewritten versions
* If a query can't be safely rewritten, it's passed through untouched

***

### Can I see what changed in my query?

Yes. You can:

* View a diff of original vs rewritten query in the dashboard
* Fetch it via the API
* Enable logs for inline comparison

```bash theme={null}
export ISOFOLD_LOG_LEVEL=debug
```

***

### What if a rewrite goes wrong?

Enable `ISOFOLD_VERIFY_MODE` to catch it:

```bash theme={null}
export ISOFOLD_VERIFY_MODE=true
```

This ensures both queries are executed and results compared. If they differ, Isofold logs the mismatch and can halt or fallback based on your config.

***

### Can I disable rewriting for certain queries?

Yes.

* Add a comment to skip:

```sql theme={null}
-- isofold:skip
SELECT * FROM sensitive_table
```

* Or create passthrough rules for tables, schemas, or patterns

***

### How much latency does Isofold add?

Minimal:

* Hosted mode (Fly.io): \~5–10ms median
* Self-hosted mode: typically sub-2ms if colocated
* No added latency for passthrough queries

***

### What permissions does Isofold need?

Hosted mode:

* Access to submit queries to your warehouse on your behalf (e.g., BigQuery service account)

Self-hosted:

* Network access to your database
* Optional: Prometheus or logging sinks

***

### Can I host Isofold myself?

Absolutely.

* Use the [self-hosted setup](/setup/self-hosted)
* Deploy via Docker, Fly.io, or GCP Marketplace
* Maintain full control over network, logs, and TLS

***

### How is billing calculated?

You’re only charged on **actual cost savings**, never on raw usage.

* See [How Billing Works](/billing/how-it-works)
* View [Savings Reports](/billing/reports)

***

### Does Isofold support data warehouses other than BigQuery, Snowflake, or Aurora?

Support is being actively expanded. Planned targets include:

* ClickHouse
* Redshift
* MotherDuck
* Postgres (native mode)

Let us know if you'd like to request support: [support@isofold.com](mailto:support@isofold.com)

***

Need help with anything else? Contact [support@isofold.com](mailto:support@isofold.com)