Known issues in Iceberg

This topic describes the known issues for Iceberg in Cloudera Data Warehouse on cloud, version 2025.0.21.2-9.

Known issues identified in the May 13, 2026 release

CDPD-101742: Hive Iceberg snapshot expiration fails for ORC LZ4/LZO tables: Hive fails to execute queries on Iceberg tables stored in ORC format with LZ4 or LZO compression when LLAP cache is enabled. The failure occurs with OWN_TASK_FAILURE and vertex failures due to an UnsupportedOperationException during ORC decompression. The snapshot expiration functionality itself works as expected and is not impacted.; For Iceberg tables, disable vectorization by setting hive.vectorized.execution.enabled=false.

CDPD-97613: Materialized view rebuild fails for Iceberg tables: Materialized view rebuild fails when the base table is an Iceberg table and the materialized view is implicitly created as an ACID table due to metastore.create.as.acid=true resulting in an error. During rebuild, no transaction is started but an entry is created in the MATERIALIZATION_REBUILD_LOCKS table and not cleared, causing subsequent attempts to fail due to an existing lock entry.; Set the metastore.create.as.acid property value to false.
This issue also occurs when the materialized view is an Iceberg table and is tracked in upstream as part of HIVE-29436
DWX-17254: Merging Iceberg branches requires a target table alias: 7.3.2; Hive supports only one level of qualifier when referencing columns. In other words only one dot is accepted. For example, select table.col from ...; is allowed. select db.table.col is not allowed. Using the merge statement to merge Iceberg branches without a target or source table alias causes an exception:
org.apache.hadoop.hive.ql.parse.SemanticException: ... Invalid table alias or column reference ...; Use an alias, for example t, for the target table.
merge into mydb.target.branch_branch1 t using mydb.source.branch_branch1 s on t.id = s.id when matched then update set value = 'matched';
Apache Jira: HIVE-28055