Mem Limit Issue (Impala)

[mrbuttons]

Hello everyone,

I'm facing an issue with an impala query of a view table that I have it connected to Power BI.

DataSource.Error: ODBC: ERROR [HY000] [Microsoft][ImpalaODBC] (110) Error while executing a query in Impala: [HY000] : Runtime Error: Rejected query from pool root.default: minimum memory reservation is greater than memory available to the query for buffer reservations. Memory reservation needed given the current plan: 2.62 GB. Adjust either the mem_limit or the pool config (max-query-mem-limit, min-query-mem-limit) for the query to allow the query memory limit to be at least 3.28 GB. Note that changing the mem_limit may also change the plan. See the query profile for more information about the per-node memory requirements.

How do I include the SET MEM_LIMIT=5g; from impala into Power BI?

Thank you!

[burakkaragoz]

Hi @mrbuttons ,

This is a tricky one. Power BI doesn’t let you pass Impala query options like SET MEM_LIMIT=5g directly in the query window or via the UI. If you try to run a SET statement in Power BI, it’ll usually throw a syntax error or just ignore the command.

But, you might be able to set the MEM_LIMIT at the ODBC connection level. If you’re using the Impala ODBC driver, you can try adding something like this to your connection string or DSN setup:

Code

QUERYOPTIONS=MEM_LIMIT=5g

Or sometimes the driver lets you set “Default Query Options” in its advanced settings — you could put MEM_LIMIT=5g there.

If that’s not working, another way is to edit the Impala server config or the pool config to increase the memory settings for all queries, but that’s more of a system admin thing.

Let me know if you want steps for setting it in ODBC or if you’re using a DSN vs direct connection string.

If my response resolved your query, kindly mark it as the Accepted Solution to assist others. Additionally, I would be grateful for a 'Kudos' if you found my response helpful.
translation and formatting supported by AI

[mrbuttons]

Sadly, I don't have access to configure it on my ODBC Connection. I'm looking for a way to do it within Power BI itself.

[v-hashadapu · Accepted solution]

Hi @mrbuttons , Thank you for reaching out to the Microsoft Community Forum.

Ask your Impala administrator to create a new view that wraps your existing query and routes it through a resource pool with a higher memory limit. That pool should have min-query-mem-limit set to at least 3.28 GB, based on the error you're seeing.

Once the view is in place, you can connect to it in Power BI just like any other table or view, no changes needed on your side. This works because Impala handles memory allocation server-side, and Power BI doesn’t support SET commands or hints like /*+ SET_VAR */ for MEM_LIMIT.

If this helped solve the issue, please consider marking it “Accept as Solution” so others with similar queries may find it more easily. If not, please share the details, always happy to help.
Thank you.