system.part_log table is created only if the part_log server setting is specified.
system.part_log table contains the following columns:
event_type(Enum) — Type of the event that occurred with the data part. Can have one of the following values:
NEW_PART— Inserting of a new data part.
MERGE_PARTS— Merging of data parts.
DOWNLOAD_PART— Downloading a data part.
REMOVE_PART— Removing or detaching a data part using DETACH PARTITION.
MUTATE_PART— Mutating of a data part.
MOVE_PART— Moving the data part from the one disk to another one.
event_date(Date) — Event date.
event_time(DateTime) — Event time.
duration_ms(UInt64) — Duration.
database(String) — Name of the database the data part is in.
table(String) — Name of the table the data part is in.
part_name(String) — Name of the data part.
partition_id(String) — ID of the partition that the data part was inserted to. The column takes the ‘all’ value if the partitioning is by
rows(UInt64) — The number of rows in the data part.
size_in_bytes(UInt64) — Size of the data part in bytes.
merged_from(Array(String)) — An array of names of the parts which the current part was made up from (after the merge).
bytes_uncompressed(UInt64) — Size of uncompressed bytes.
read_rows(UInt64) — The number of rows was read during the merge.
read_bytes(UInt64) — The number of bytes was read during the merge.
error(UInt16) — The code number of the occurred error.
exception(String) — Text message of the occurred error.
system.part_log table is created after the first inserting data to the