prestodb/presto · error · PrestoException

ICEBERG_TRANSACTION_CONFLICT_ERROR

ICEBERG_TRANSACTION_CONFLICT_ERROR

Error message

 cannot be called within a transaction (use autocommit mode) in Iceberg connector.

What it means

Thrown by IcebergAbstractMetadata.shouldRunInAutoCommitTransaction when a statement that only supports autocommit execution (e.g. certain materialized view or table-maintenance operations) is issued inside an explicit multi-statement transaction. The Iceberg connector cannot run these operations within a user transaction.

Source

Thrown at presto-iceberg/src/main/java/com/facebook/presto/iceberg/IcebergAbstractMetadata.java:2893

                    .commit();
        }
        catch (RuntimeException e) {
            throw new PrestoException(ICEBERG_INCOMPATIBLE_COLUMN_TYPE, "Failed to set column type: " + firstNonNull(e.getMessage(), e), e);
        }
    }

    protected void openCreateTableTransaction(SchemaTableName tableName, Transaction transaction)
    {
        transactionContext.registerTransaction(tableName, transaction);
    }

    /**
     * Check and ensure that the specified statement can only run in a transaction with autocommit context set to true.
     * */
    protected void shouldRunInAutoCommitTransaction(String statement)
    {
        if (!transactionContext.isAutoCommitContext()) {
            throw new PrestoException(ICEBERG_TRANSACTION_CONFLICT_ERROR, statement + " cannot be called within a transaction (use autocommit mode) in Iceberg connector.");
        }
    }
}

View on GitHub (pinned to 55bb57d202)

Solutions

1. Run the statement outside any explicit transaction: COMMIT/ROLLBACK the current transaction first, then execute in autocommit mode
2. Ensure the client/session has autocommit enabled (e.g. remove START TRANSACTION around the DDL)
3. Restructure application logic so this Iceberg operation is executed as a standalone statement

Example fix

// before
START TRANSACTION;
CREATE MATERIALIZED VIEW mv AS SELECT ...;
COMMIT;
// after
-- execute directly, autocommit on
CREATE MATERIALIZED VIEW mv AS SELECT ...;

// in client code, ensure autocommit before running Iceberg DDL
if (connection.getTransactionIsolation() != TRANSACTION_NONE && !connection.getAutoCommit()) {
    throw new IllegalStateException("Commit/rollback the transaction before running this Iceberg statement");
}

try { stmt.execute(ddl); } catch (PrestoException e) { if ("ICEBERG_TRANSACTION_CONFLICT_ERROR".equals(e.getErrorCode().getName())) { connection.setAutoCommit(true); /* re-run */ } else throw e; }

When it happens

Trigger: Executing a restricted statement (the operation name is prepended to the message) while inside START TRANSACTION ... without autocommit, i.e. transactionContext.isAutoCommitContext() is false.

Common situations: Wrapping CREATE/DROP MATERIALIZED VIEW or similar Iceberg DDL in an explicit transaction in a session or tool that keeps a transaction open; ORM/framework-managed sessions with autocommit disabled.

Related errors

• dropping a table added/modified in the same transaction is n
• HIVE_METASTORE_ERROR
• NOT_FOUND
• ALREADY_EXISTS
• INVALID_TABLE_PROPERTY

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/ac379d5fb5160193. Report an issue: GitHub.