Calcite push-down operation

[勾王敏浩 <gw...@mails.tsinghua.edu.cn>]

Hi，
My name is Wangminhao Gou. I've read the CSV example of calcite and written several other adapters following the CSV adapter(However, all are scannable). Now I'm going to write the adapter for IoTDB. However，Considering performance, we don't want to just implement ScannableTable. We want to push as many operations as possible down to IoTDB.
Here are my questions:
1.We want to get the user's query statement first. Turn this query statement into an IoTDB recognizable query. Use IoTDB to process the query and get a resultSet. Then use this resultSet to perform scan operations and stitch it together into the final resultSet of calcite. How can I get the query in the adapter and can I get the resultSet first and then put it together?
2.If my above considerations cannot be realized, is there any other way to push queries down to the IoTDB database?


Best Regards,
Wangminhao Gou

Re: Calcite push-down operation

[Lai Zhou <hh...@gmail.com>]

@Wangminhao Gou
I think you can reference the JdbcConvention , that would push queries to
JDBC datasource as much as possible,.



勾王敏浩 <gw...@mails.tsinghua.edu.cn> 于2019年5月9日周四 下午4:18写道：

> Hi，
> My name is Wangminhao Gou. I've read the CSV example of calcite and
> written several other adapters following the CSV adapter(However, all are
> scannable). Now I'm going to write the adapter for IoTDB.
> However，Considering performance, we don't want to just implement
> ScannableTable. We want to push as many operations as possible down to
> IoTDB.
> Here are my questions:
> 1.We want to get the user's query statement first. Turn this query
> statement into an IoTDB recognizable query. Use IoTDB to process the query
> and get a resultSet. Then use this resultSet to perform scan operations and
> stitch it together into the final resultSet of calcite. How can I get the
> query in the adapter and can I get the resultSet first and then put it
> together?
> 2.If my above considerations cannot be realized, is there any other way to
> push queries down to the IoTDB database?
>
>
> Best Regards,
> Wangminhao Gou
>
>