[Bug] Flink VARIANT NOT NULL column is stored as nullable #10616

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• I searched in the issues and found nothing similar.

Paimon version

master (5d019f5)

Compute Engine

Flink 2.1 / 2.2

Minimal reproduce step

CREATE TABLE t (id INT, v VARIANT NOT NULL);
INSERT INTO t VALUES (1, CAST(NULL AS VARIANT));
SELECT * FROM t;

What doesn't meet your expectations?

The insert succeeds and the table holds a NULL in a column declared NOT NULL. LogicalTypeToDataType.visit(VariantType) always creates a nullable Paimon VariantType, so the NOT NULL constraint is not stored, Flink reads the column back as nullable and does not enforce it, and other engines see a nullable column too.

Anything else?

No response

Are you willing to submit a PR?

• I'm willing to submit a PR!