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distributed_ddl_queue

Contains information about distributed ddl queries (ON CLUSTER clause) that were executed on a cluster.

Columns:

  • entry (String) — Query id.
  • entry_version (Nullable(UInt8)) - Version of the entry
  • initiator_host (Nullable(String)) - Host that initiated the DDL operation
  • initiator_port (Nullable(UInt16)) - Port used by the initiator
  • cluster (String) — Cluster name.
  • query (String) — Query executed.
  • settings (Map(String, String)) - Settings used in the DDL operation
  • query_create_time (DateTime) — Query created time.
  • host (String) — Hostname
  • port (UInt16) — Host Port.
  • status (Enum8) — Status of the query.
  • exception_code (Enum8) — Exception code.
  • exception_text (Nullable(String)) - Exception message
  • query_finish_time (DateTime) — Query finish time.
  • query_duration_ms (UInt64) — Duration of query execution (in milliseconds).

Example

SELECT *
FROM system.distributed_ddl_queue
WHERE cluster = 'test_cluster'
LIMIT 2
FORMAT Vertical

Query id: f544e72a-6641-43f1-836b-24baa1c9632a

Row 1:
──────
entry:             query-0000000000
entry_version:     5
initiator_host:    clickhouse01
initiator_port:    9000
cluster:           test_cluster
query:             CREATE DATABASE test_db UUID '4a82697e-c85e-4e5b-a01e-a36f2a758456' ON CLUSTER test_cluster
settings:          {'max_threads':'16','use_uncompressed_cache':'0'}
query_create_time: 2023-09-01 16:15:14
host:              clickhouse-01
port:              9000
status:            Finished
exception_code:    0
exception_text:    
query_finish_time: 2023-09-01 16:15:14
query_duration_ms: 154

Row 2:
──────
entry:             query-0000000001
entry_version:     5
initiator_host:    clickhouse01
initiator_port:    9000
cluster:           test_cluster
query:             CREATE DATABASE test_db UUID '4a82697e-c85e-4e5b-a01e-a36f2a758456' ON CLUSTER test_cluster
settings:          {'max_threads':'16','use_uncompressed_cache':'0'}
query_create_time: 2023-09-01 16:15:14
host:              clickhouse-01
port:              9000
status:            Finished
exception_code:    630
exception_text:    Code: 630. DB::Exception: Cannot drop or rename test_db, because some tables depend on it:
query_finish_time: 2023-09-01 16:15:14
query_duration_ms: 154

2 rows in set. Elapsed: 0.025 sec.