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Posted to issues@flink.apache.org by "Shengkai Fang (Jira)" <ji...@apache.org> on 2020/10/14 09:36:00 UTC
[jira] [Updated] (FLINK-19639) Support
SupportsNestedProjectionPushDown in planner
[ https://issues.apache.org/jira/browse/FLINK-19639?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Shengkai Fang updated FLINK-19639:
----------------------------------
Description:
Support to push nested projection into {{TableSourceScan}}. But it may cause name conflicts in some situaion. For example, we create the table with ddl
{code:sql}
CREATE TABLE NestedTable (
nest1 ROW<a INT>,
nest2 ROW<a INT>
)
{code}
and with query
{code:sql}
SELECT nest1.a, nest2.a from NestedTable
{code}
and we will get 2 {{`a`}} in the new schema when pushing projection.
Here we use {{'_'}} to concatenate the names of all levels as the name of the nested fields. In this example, we will get fields {{nest1_a, nest2_a}} in the new schema.
was:
Support to push nested projection into {{TableSourceScan}}. But it may cause name conflicts in some situaion. For example, we create table with ddl
{code:sql}
CREATE TABLE NestedTable (
nest1 ROW<a INT>,
nest2 ROW<a INT>
)
{code}
and with query
{code:sql}
SELECT nest1.a, nest2.a from NestedTable
{code}
and we will get 2 {{`a`}} in the new schema when pushing projection.
Here we use {{'_'}} to concatenate the names of all levels as the name of the nested fields. In this example, we will get fields {{nest1_a, nest2_a}} in the new schema.
> Support SupportsNestedProjectionPushDown in planner
> ---------------------------------------------------
>
> Key: FLINK-19639
> URL: https://issues.apache.org/jira/browse/FLINK-19639
> Project: Flink
> Issue Type: New Feature
> Components: Table SQL / Planner
> Reporter: Shengkai Fang
> Priority: Major
>
> Support to push nested projection into {{TableSourceScan}}. But it may cause name conflicts in some situaion. For example, we create the table with ddl
> {code:sql}
> CREATE TABLE NestedTable (
> nest1 ROW<a INT>,
> nest2 ROW<a INT>
> )
> {code}
> and with query
> {code:sql}
> SELECT nest1.a, nest2.a from NestedTable
> {code}
> and we will get 2 {{`a`}} in the new schema when pushing projection.
> Here we use {{'_'}} to concatenate the names of all levels as the name of the nested fields. In this example, we will get fields {{nest1_a, nest2_a}} in the new schema.
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