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系统。零件

包含有关的部分信息 MergeTree 桌子

每行描述一个数据部分。

列:

  • partition (String) – The partition name. To learn what a partition is, see the description of the ALTER 查询。

    格式:

    • YYYYMM 用于按月自动分区。
    • any_string 手动分区时。
  • name (String) – Name of the data part.

  • active (UInt8) – Flag that indicates whether the data part is active. If a data part is active, it’s used in a table. Otherwise, it’s deleted. Inactive data parts remain after merging.

  • marks (UInt64) – The number of marks. To get the approximate number of rows in a data part, multiply marks 通过索引粒度(通常为8192)(此提示不适用于自适应粒度)。

  • rows (UInt64) – The number of rows.

  • bytes_on_disk (UInt64) – Total size of all the data part files in bytes.

  • data_compressed_bytes (UInt64) – Total size of compressed data in the data part. All the auxiliary files (for example, files with marks) are not included.

  • data_uncompressed_bytes (UInt64) – Total size of uncompressed data in the data part. All the auxiliary files (for example, files with marks) are not included.

  • marks_bytes (UInt64) – The size of the file with marks.

  • modification_time (DateTime) – The time the directory with the data part was modified. This usually corresponds to the time of data part creation.|

  • remove_time (DateTime) – The time when the data part became inactive.

  • refcount (UInt32) – The number of places where the data part is used. A value greater than 2 indicates that the data part is used in queries or merges.

  • min_date (Date) – The minimum value of the date key in the data part.

  • max_date (Date) – The maximum value of the date key in the data part.

  • min_time (DateTime) – The minimum value of the date and time key in the data part.

  • max_time(DateTime) – The maximum value of the date and time key in the data part.

  • partition_id (String) – ID of the partition.

  • min_block_number (UInt64) – The minimum number of data parts that make up the current part after merging.

  • max_block_number (UInt64) – The maximum number of data parts that make up the current part after merging.

  • level (UInt32) – Depth of the merge tree. Zero means that the current part was created by insert rather than by merging other parts.

  • data_version (UInt64) – Number that is used to determine which mutations should be applied to the data part (mutations with a version higher than data_version).

  • primary_key_bytes_in_memory (UInt64) – The amount of memory (in bytes) used by primary key values.

  • primary_key_bytes_in_memory_allocated (UInt64) – The amount of memory (in bytes) reserved for primary key values.

  • is_frozen (UInt8) – Flag that shows that a partition data backup exists. 1, the backup exists. 0, the backup doesn’t exist. For more details, see FREEZE PARTITION

  • database (String) – Name of the database.

  • table (String) – Name of the table.

  • engine (String) – Name of the table engine without parameters.

  • path (String) – Absolute path to the folder with data part files.

  • disk (String) – Name of a disk that stores the data part.

  • hash_of_all_files (String) – sipHash128 的压缩文件。

  • hash_of_uncompressed_files (String) – sipHash128 未压缩的文件(带标记的文件,索引文件等。).

  • uncompressed_hash_of_compressed_files (String) – sipHash128 压缩文件中的数据,就好像它们是未压缩的。

  • bytes (UInt64) – Alias for bytes_on_disk.

  • marks_size (UInt64) – Alias for marks_bytes.