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…Greenplum Add support for custom scan nodes, allowing extensions to define their own scan strategies that integrate with the planner, executor, EXPLAIN, and GPDB's CDB dispatch pipeline. New node types: T_CustomScan, T_CustomScanState, T_CustomPath, T_ExtensibleNode. New files: extensible.h/c (registration framework), nodeCustom.h/c (executor callbacks). Full binary serialization support for plan dispatch to segments. Includes set_rel_pathlist_hook for planner extensibility and a test extension (custom_scan_test) that replaces SeqScan with a CustomScan to validate the pipeline end-to-end.
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Apr 8, 2026
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| if (tlistvarno == INDEX_VAR) | ||
| ExecAssignScanProjectionInfo(&css->ss); | ||
| else | ||
| ExecAssignScanProjectionInfo(&css->ss); |
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What about two identical branches? I also don't see this code in the upstream, can you please point to the code you are porting from?
I see that upstream has different code in some places but I don't know if it's okay or not.
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It is from Postgresql code master branch
I tried to move custom nodes in gpdb because some features requires their own algorithms or path preparation logic.
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Port CustomScan and ExtensibleNode infrastructure from PostgreSQL to Greenplum
custom_scan_test extension is an example how to use it and simple example to check that it works