Support for OFFSET Pushdown in Custom Trino Connector

[lihonosov]

I’m working on a custom Trino connector (query external data source via HTTP protocol) and would like to push down the OFFSET parameter directly to the data source. However, it seems that Trino might not support this functionality fully at the moment.

For example, when I run a query like:

SELECT * FROM custom_connector_table OFFSET 1 LIMIT 1

the ConnectorMetadata.applyLimit method only receives limit = 2, without a clear way to distinguish between the OFFSET and LIMIT values separately.

Is there a way to directly access the values of both OFFSET and LIMIT in the current Trino API, or is there another recommended approach for implementing OFFSET pushdown in a custom connector?

Any guidance on this would be greatly appreciated!

[chenjian2664]

@hashhar @kokosing @ebyhr
Do you think it is worth to add a rule to pushdown the offset with limit, if yes I wanna take this

[kokosing]

I haven't heard much about a demand for this.

[lihonosov]

It also happens with the Postgres connector:

Query log from Postgres:

So, instead of returning 1 row, Postgres will return up to 1,001 rows

[chenjian2664]

It's because of the PushLimitThroughOffset.