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https://issues.apache.org/jira/browse/FLINK-39718?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Ran Tao updated FLINK-39718:
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    Description: 
When using a distributed pipeline source with Paimon sink, the job may fail if 
the target table does not already exist.

The failure happens in *DistributedPrePartitionOperator*. The previous 
*PaimonHashFunction* rebuilds the hash function at this stage and immediately 
accesses the external Paimon catalog to load the target table. If
  the table has not been created yet, *catalog.getTable(...)* throws 
TableNotExistException, and the job fails in the pre-partition stage.

This issue is usually not exposed in MySQL-CDC pipelines because MySQL-CDC uses 
regular topology. In that path, CreateTableEvent is handled by SchemaOperator 
first, and MetadataApplier creates the downstream table before records enter 
*RegularPrePartitionOperator*. As a result, the previous PaimonHashFunction can 
usually find the target table from the catalog.

For distributed pipeline sources, the execution order is different: 
pre-partitioning happens before the target table is created by 
*MetadataApplier* in the schema coordination phase.

 This issue is not specific to Kafka. It can affect any distributed pipeline 
source with the same execution order.

  was:
When using distributed pipeline source(such as kafka, We've implemented a kafka 
pipeline within the company, but this is a common/universal problem.) with 
Paimon sink in distributed topology, the job may fail before the sink finishes 
auto-creating the target table.

The failure happens in *DistributedPrePartitionOperator*. The previous 
*PaimonHashFunction* rebuilds the hash function at this stage and immediately 
accesses the external Paimon catalog to load the target table. However, in the 
auto-created table case, the sink-side table creation has not happened yet, so 
catalog.getTable(...) throws TableNotExistException and the job fails in 
pre-partition stage.

This issue is usually not exposed in MySQL-CDC pipelines because MySQL-CDC uses 
regular topology. In that path, CreateTableEvent is handled by SchemaOperator 
first, and the sink-side MetadataApplier creates the downstream table before 
records enter RegularPrePartitionOperator. As a result, the old 
PaimonHashFunction can usually find the target table from catalog.

*A distributed pipeline source behaves differently because it uses a 
distributed topology, where pre-partitioning happens before the target table is 
created by the sink MetadataApplier in the schema coordination phase.*

Paimon or other pipeline sinks that support automatic table creation should 
support distributed topologies, even if there isn't currently a connector for a 
distributed pipeline source.


> [pipeline][paimon] Paimon pipeline sink fails with distributed source when 
> target table does not exist
> ------------------------------------------------------------------------------------------------------
>
>                 Key: FLINK-39718
>                 URL: https://issues.apache.org/jira/browse/FLINK-39718
>             Project: Flink
>          Issue Type: Bug
>          Components: Flink CDC
>            Reporter: Ran Tao
>            Priority: Major
>
> When using a distributed pipeline source with Paimon sink, the job may fail 
> if the target table does not already exist.
> The failure happens in *DistributedPrePartitionOperator*. The previous 
> *PaimonHashFunction* rebuilds the hash function at this stage and immediately 
> accesses the external Paimon catalog to load the target table. If
>   the table has not been created yet, *catalog.getTable(...)* throws 
> TableNotExistException, and the job fails in the pre-partition stage.
> This issue is usually not exposed in MySQL-CDC pipelines because MySQL-CDC 
> uses regular topology. In that path, CreateTableEvent is handled by 
> SchemaOperator first, and MetadataApplier creates the downstream table before 
> records enter *RegularPrePartitionOperator*. As a result, the previous 
> PaimonHashFunction can usually find the target table from the catalog.
> For distributed pipeline sources, the execution order is different: 
> pre-partitioning happens before the target table is created by 
> *MetadataApplier* in the schema coordination phase.
>  This issue is not specific to Kafka. It can affect any distributed pipeline 
> source with the same execution order.



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