Slow connection from Amazon Redshift to Power BI Pro

[harheeni]

Hi everyone,

I'm experiencing very slow connection performance when connecting Amazon Redshift to Power BI Pro.

The connection takes a long time to establish, and queries are loading much slower than expected. I'm trying to understand whether this is a common issue or if there are recommended optimizations.

Has anyone encountered similar behavior?
Are there best practices for improving Redshift performance with Power BI Pro?

Any guidance would be greatly appreciated.

Thank you.

[V-yubandi-msft]

Hi @harheeni ,

We haven’t received a response from your end yet. Please let us know whether the issue has been resolved or if you’re still facing any difficulties. Feel free to reach out if you need further assistance.

Thank you.

[V-yubandi-msft]

Hi @harheeni ,

If you get a chance, please review the responses shared by @GilbertQ . They have correctly pointed out the key points, so kindly check and let us know if you need any additional details.

Thank you all for your valuable support @GilbertQ , @MohitsinghMS .

Regards,

Yugandhar.

[GilbertQ]

Hi @harheeni 

Could you please let us know how you are connecting to Redshift and if you're using Import or Directquery as all of these could play into the reasons as to why your reports are running slowly. Once we have that information we could assist you further. For example, using Directquery means you're relying on Redshift and if Redshift is running slowly, well then your reports will be running slowly. Likewise if you are connecting by a gateway it could be potentially there's an issue on the gateway connectivity that's making it run slowly, whilst when using import, once the data is imported it should always run quicker because it's all running within the Power BI service.

[MohitsinghMS · Accepted solution]

Hi! This is a fairly common challenge when connecting Redshift to Power BI Pro. Here are a few things that can make a big difference:

1. Use DirectQuery vs Import Mode wisely If you're using DirectQuery, switch to Import Mode where possible. Import Mode loads data into Power BI's in-memory engine (VertiPaq), which is significantly faster for most use cases.

2. Optimize your Redshift queries

• Use materialized views or pre-aggregated tables instead of querying raw large tables.
• Avoid SELECT * — only pull the columns you actually need.
• Apply filters at the source level to reduce data volume.

3. Use Distribution & Sort Keys in Redshift Make sure your Redshift tables have proper distribution keys and sort keys aligned with how Power BI queries them. This dramatically reduces query execution time.

4. Use the Official ODBC/JDBC Driver Ensure you're using the latest Amazon Redshift ODBC driver. Outdated drivers can cause connection delays.

5. Enable Query Folding When using Power Query, ensure query folding is working so transformations are pushed back to Redshift rather than processed locally.

6. Check Network Latency If your Redshift cluster is in a different AWS region than your location or Power BI gateway, latency can be a major factor. Consider using an on-premises data gateway closer to the cluster.

7. Use a Power BI Gateway For scheduled refreshes, an on-premises data gateway can stabilize and speed up connections considerably.