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serprex
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Jun 16, 2026
For a normal foreign scan, it's fine to let Postgres clean up the `batch_cxt` when it clears the memory context. But for a scan that repeatedly re-scans (e.g., `clickhouseEndForeignScan` is called via the `ReScanForeignScan` callback), it Postgres doesn't clear the context until the query finishes. Since pg_clickhouse creates the `ChFdwScanState` anew for each scan (in `clickhouseBeginForeignScan()`), that memory from previous scans would just hang around. Delete `batch_cxt` in `clickhouseEndForeignScan` to ensure the context is cleaned up for every scan. Resolves #273.
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For a normal foreign scan, it's fine to let Postgres clean up the
batch_cxtwhen it clears the memory context. But for a scan that repeatedly re-scans (e.g.,clickhouseEndForeignScanis called via theReScanForeignScancallback), it Postgres doesn't clear the context until the query finishes. Since pg_clickhouse creates theChFdwScanStateanew for each scan (inclickhouseBeginForeignScan()), that memory from previous scans would just hang around.Delete
batch_cxtinclickhouseEndForeignScanto ensure the context is cleaned up for every scan. Resolves #273.