Data Warehouse troubleshooting

This page covers troubleshooting for Data Warehouse. For setup, see the installation guides.

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How can I see why my syncs are failing?

From the source page, click the source that's failing, scroll over to the Status column and hover over the error message.

Viewing the error message for a failed sync

You can also click the Syncs tab and expand any failed sync to see all the logs.

Why is "Pull new schemas" not finding any tables?

When you click Pull new schemas on an external data source (Postgres, MySQL, Redshift, etc.) and see a warning that no tables were found, this typically means:

Missing SELECT permissions - The database user configured for the source doesn't have SELECT access to the target schema.
Incorrect configuration - The schema name, credentials, or connection details in your source settings are wrong.

To fix this, check that your database user has SELECT permissions on the target schema and its tables, and verify that your source credentials and configuration are correct.

Why does "Pull new schemas" show "no schema changes"?

If you click Pull new schemas and see a success message saying there are no schema changes, this means the connection to your source is working correctly and all tables in the source schema are already being tracked.

This is expected behavior when your source configuration is up to date. New tables only appear if they've been added to the source database since your last refresh.

Why am I seeing an error when pulling schemas?

When Pull new schemas fails, the error message shows the specific underlying cause instead of a generic failure message. Common errors include:

Authentication failures - Invalid credentials or expired passwords.
Connection errors - Network issues, firewall rules, or the database server being unreachable.
Permission denied - The user lacks access to the specified schema or database.

Use the error details in the toast notification to diagnose and fix the issue in your database configuration.

How do I speed up my SQL queries?

Reduce the date range you're querying.
Add more specific filters with WHERE clauses.
Use materialized views.

We have other suggestions in our product analytics docs.

How do I run partial SQL queries?

If you want to run a part of your query in the SQL editor, highlight the part you want to run and hit CMD + Enter (Mac) or CTRL + Enter (Windows).

This is useful if you have a complex query and you want to test parts of it without running the whole query.

Why is my CSV data not parsing correctly?

If your CSV data appears garbled, has missing columns, or shows unexpected characters, it may be due to incorrect quote handling settings.

When linking a CSV file, PostHog provides a CSV quote handling option with two modes:

RFC 4180 double quotes - Use this when your CSV uses standard double-quote escaping (e.g., "Hello ""World""" becomes Hello "World")
Literal quotes - Use this when quotes in your data should be treated as regular characters (default)

To fix parsing issues, try recreating the table with the other quote handling option selected.

Why am I getting "Some files in the bucket are archived"?

This error occurs when files in your S3 bucket are stored in S3 Glacier or S3 Intelligent-Tiering archive storage classes. These storage classes are designed for long-term archival and cannot be accessed directly.