Hi team 👋 I'm writing a custom Trino connector to read from our Pinot cluster and I'm running into an issue when trying to use

LASTWITHTIME

. The first time I run the query (

SELECT * FROM catalog.schema."SELECT LASTWITHTIME(dataColumnName, timeColumnName, 'STRING') FROM tableName WHERE column = 'someColumnValue' LIMIT 10";

) I get the following error:

java.lang.ExceptionInInitializerError
	at org.apache.pinot.common.function.TransformFunctionType.getTransformFunctionType(TransformFunctionType.java:106)

Any consecutive runs of the query produce the following error:

java.lang.NoClassDefFoundError: Could not initialize class org.apache.pinot.common.function.FunctionRegistry
	at org.apache.pinot.common.function.TransformFunctionType.getTransformFunctionType(TransformFunctionType.java:106)

Other queries, including dynamic queries work okay. I am using Pinot version 0.9.3. Has anyone come across this before? Any help would be appreciated, many thanks in advance!

Is that a nested query? Pinot doesn’t support nested queries at the moment.

It's a dynamic query where we're pushing down the whole query to Pinot. For example this works:

SELECT * FROM catalog.schema."SELECT columnName FROM table LIMIT 1";

the class isn't loading, which is interesting

Hi @Richard Startin thanks for replying! I don't see any errors in the logs during initialization or running other queries, it seems to only throw when I run that particular query

Seems like the inner query runs on Pinot successfully, so the transform function is indeed part of 0.9.x

Yup -

explain analyze

throws this error too:

Query 20220307_173536_00009_bawgb failed: java.lang.NoClassDefFoundError: Could not initialize class org.apache.pinot.common.function.FunctionRegistry

NoClassDefFoundError

means that the class could not be loaded but not because the classfile is missing

Thank you everyone for all your help in this matter. Following the advice here I looked into my connector code and realised the maven-shade-plugin was filtering out classes I needed for the initialization of the FunctionRegistry. I have now resolved the issue however I am still not able to run the query successfully - it's now failing with the following error:

Unexpected aggregate expression: 'lastwithtime(id,timestamp,'string')'

I have opened this issue as it doesn't look like the FunctionRegistry contains LASTWITHTIME when it's initialized from my logs. Thank you all again!

@Elon could we add this function support in the connector?

Yes, sure!

Thanks @Elon! I responded to your comment on the issue

nice:) What data type should the

id

field be? Assuming

timestamp

is a long, right?

Also bear in mind lastwithtime seems to have two function signatures, one where it requires 2 args, and one where it requires 3. I’m not entirely sure why the one with 3 is necessary

the

id

field is a String and yep the

timestamp

is a Long

thanks!

Interested by that. Tried the same query and failed Trino trino-372 and pinot-0.9.3

This is great, but we did fork the connector and upgrade it ourselves. We’ll compare the two and see if we missed anything, thank you for the help

Hi @Elon thank you so much for getting this change in! We've just brought these into our connector and still seeing

Query 20220323_155125_00000_kskyw failed: Unexpected aggregate expression: 'lastwithtime(id,timestamp,'string')'

Looks like the

lastwithtime

function isn't part of the

TransformFunctionType

enum class (link). Could this be causing the issue?

That sounds likely, I will check. Thanks for catching this!

Thanks @Elon! This is the query we're using:

SELECT * FROM catalog.default."SELECT LASTWITHTIME(id, timestamp, 'STRING') FROM table WHERE field = 'something' LIMIT 10";

The connector we're using is basically a fork from Trino 371, we upgraded Pinot version to 0.9.3 and I've just brought in all the changes in your PR above and it's still coming back with that error

Ok, I will investigate and add this as a unit test then:) I'll update you shortly

Thank you!

The pr should be landing very soon - we updated it to support 0.10.0.

That's awesome @Elon. Any ETA on when that would be available?