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    Data Lake Formation:Data structures

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    Data Lake Formation:Data structures

    Last Updated:Mar 26, 2026

    This topic describes the data structures used by the DLF metadata API.

    GetViewResponse

    Name Type Description Example
    - object The details of the view. -
    id string The view ID. 1
    name string The view name. view_demo
    schema ViewSchema The view structure. -

    GetTableResponse

    Name Type Description Example
    - object The details of the table. -
    id string The UUID of the table. 1
    name string The table name. table_test
    path string The table path. oss://clg-paimon-xxx/db-xxx/tbl-xxxx
    isExternal string Whether the table is an external table. true
    schemaId string The ID of the table schema. 1
    schema Schema The table schema. -
    owner string The owner of the table. ALIYUN$1234567
    createdAt long The time when the table was created. Unix timestamp in milliseconds. 1741266704867
    createdBy string The user who created the table. acs:ram:1234567:root
    updatedAt long The time when the table was last updated. Unix timestamp in milliseconds. 1741266704867
    updatedBy string The user who last updated the table. acs:ram:1045689747920334:root

    Partition

    Name Type Description Example
    - object The details of the partition. -
    spec map The key-value pairs of the partition values. {"year":"2025"}
    recordCount long The number of records in the partition. 1
    fileSizeInBytes long The total size of the partition files, in bytes. 1024
    fileCount long The number of files in the partition. 1
    lastFileCreationTime long The creation time of the most recent file. Unix timestamp in milliseconds. 1741762385537

    TableSnapshot

    Name Type Description Example
    - object The table snapshot information. -
    snapshot Snapshot The snapshot details. -
    recordCount long The total number of records. 1
    fileSizeInBytes long The total file size, in bytes. 1024
    fileCount long The total number of files. 24
    lastFileCreationTime long The creation time of the most recent file. Unix timestamp in milliseconds. 1741701564261

    Identifier

    Name Type Description Example
    - object The table identifier. -
    databaseName string The database name. db_test
    tableName string The table name. table_test

    Schema

    Name Type Description Example
    - object The table schema. -
    fields array The list of table fields. Each element is a DataField. -
    partitionKeys array The list of partition key names. ["partition_key1", "partition_key2"]
    primaryKeys array The list of primary key names. ["pk1", "pk2"]
    options map The table options as key-value pairs. {"manifest.merge-min-count": "10"}
    comment string The table comment. test_comment

    DataField

    Name Type Description Example
    - object A table field definition. -
    id integer The field ID. 1
    name string The field name. col_name
    type DataType The field data type. -

    DataType

    A DataType is one of the following:

    Name Type Description Example
    - object The data type. Exactly one of the following fields is set. -
    primitiveType string A primitive data type. Valid values: BIGINT, BINARY, BOOLEAN, CHAR, DATE, DECIMAL, DOUBLE, FLOAT, INT, SMALLINT, TIMESTAMP, TINYINT, VARBINARY, VARCHAR, VARIANT. BIGINT
    arrayType ArrayType An array type. -
    multisetType MultisetType A multiset type. -
    mapType MapType A map type. -
    rowType RowType A row type. -

    SchemaChange

    A SchemaChange describes a single schema evolution operation. Each operation is identified by its type field. Use the following table to determine which subtype to use:

    Type value Structure Operation
    setOption SetOption Sets a table option.
    removeOption RemoveOption Removes a table option.
    updateComment UpdateComment Updates the table comment.
    addColumn AddColumn Adds a column.
    renameColumn RenameColumn Renames a column.
    dropColumn DropColumn Drops a column.
    updateColumnComment UpdateColumnComment Updates a column comment.
    updateColumnType UpdateColumnType Updates a column type.
    updateColumnPosition UpdateColumnPosition Updates a column position.
    updateColumnNullability UpdateColumnNullability Updates column nullability.

    ViewSchema

    Name Type Description Example
    - object The view structure. -
    fields array The list of view fields. Each element is a DataField. -
    query string The view query statement. -
    dialects map\<string, string\> The SQL dialects and their corresponding query statements. {"flink": "xxxx", "spark": "xxxx"}
    comment string The view comment. -
    options map The view options as key-value pairs. -

    Snapshot

    Name Type Nullable Description Example
    - object - The snapshot details. -
    version integer Yes The snapshot file format version. The current version is 3. 3
    id long No The snapshot ID. 6
    schemaId long No The ID of the table schema at the time of this snapshot. 0
    baseManifestList string No The base manifest list. manifest-list-0c6fcaa1-b6bc-413d-9634-6471cce4f37e-2
    baseManifestListSize long Yes The size of the base manifest list, in bytes. 845
    deltaManifestList string No The manifest list recording all new changes in this snapshot. manifest-list-0c6fcaa1-b6bc-413d-9634-6471cce4f37e-3
    deltaManifestListSize long Yes The size of the delta manifest list, in bytes. 759
    changelogManifestList string Yes The manifest list recording all changelogs generated in this snapshot. manifest-list-0c6fcaa1-b6bc-413d-9634-6471cce4f37e-4
    changelogManifestListSize long Yes The size of the changelog manifest list, in bytes. 759
    indexManifest string Yes The manifest recording all index files for this table. index-manifest-7cbdaa47-9578-43ac-ae6e-a7ec0486bba8-0
    commitUser string No Usually a UUID, used to resume stream writing. 446aac61-bd5c-4fa0-8b14-846fa8810651
    commitIdentifier long No The transaction ID for stream writing. 9223372036854775807
    commitKind string No The type of stream writing. Valid values: APPEND, COMPACT, OVERWRITE, ANALYZE. COMPACT
    timeMillis long No The commit timestamp in milliseconds. 1741701564261
    logOffsets Map\<Integer, Long\> Yes The log offsets at the time of this commit. {0: 1L, 1: 3L}
    totalRecordCount long Yes The total number of records across all changes in this snapshot. 1024
    deltaRecordCount long Yes The number of records in the new changes of this snapshot. 10
    changelogRecordCount long Yes The number of changelog records generated in this snapshot. 100
    watermark long Yes The watermark value. -9223372036854775808
    statistics string Yes The name of the statistics file for this table. -

    Instant

    An Instant is one of the following:

    Name Type Description Example
    - object A point-in-time reference. Exactly one of the following fields is set. -
    snapshotInstant SnapshotInstant A snapshot-based instant. 1
    tagInstant TagInstant A tag-based instant. test_tag

    SnapshotInstant

    Name Type Description Example
    - object A snapshot-based point-in-time reference. -
    snapshotId long The snapshot ID. 1

    TagInstant

    Name Type Description Example
    - object A tag-based point-in-time reference. -
    tagName string The tag name. 1

    ArrayType

    Name Type Description Example
    - object An array data type. -
    type string The type identifier. Pattern: ^ARRAY.*. ARRAY
    element DataType The element data type. INT

    MultisetType

    Name Type Description Example
    - object A multiset data type. -
    type string The type identifier. Pattern: ^MULTISET.*. MULTISET
    element DataType The element data type. BIGINT

    MapType

    Name Type Description Example
    - object A map data type. -
    type string The type identifier. Pattern: ^MAP.*. MAP
    key DataType The key data type. STRING
    value DataType The value data type. BOOLEAN

    RowType

    Name Type Description Example
    - object A row data type. -
    type string The type identifier. Pattern: ^ROW.*. ROW
    fields array The list of fields. Each element is a DataField. -

    SetOption

    Name Type Description Example
    - object Sets a table option. -
    type string Fixed value: setOption. setOption
    key string The option key. manifest.delete-file-drop-stats
    value string The option value. true

    RemoveOption

    Name Type Description Example
    - object Removes a table option. -
    type string Fixed value: removeOption. removeOption
    key string The option key to remove. manifest.delete-file-drop-stats

    UpdateComment

    Name Type Description Example
    - object Updates the table comment. -
    type string Fixed value: updateComment. updateComment
    comment string The new table comment. comment_test

    AddColumn

    Name Type Description Example
    - object Adds a column to the table. -
    type string Fixed value: addColumn. addColumn
    fieldNames array The path to the new field, as a list of field name segments. -
    dataType DataType The data type of the new field. -
    comment string The field comment. comment_test
    move Move The position to insert the new field. -

    RenameColumn

    Name Type Description Example
    - object Renames a column. -
    type string Fixed value: renameColumn. renameColumn
    fieldNames array The path to the field, as a list of field name segments. -
    newName string The new field name. new_col_test

    DropColumn

    Name Type Description Example
    - object Drops a column. -
    type string Fixed value: dropColumn. dropColumn
    fieldNames array The path to the field, as a list of field name segments. -

    UpdateColumnComment

    Name Type Description Example
    - object Updates a column comment. -
    type string Fixed value: updateColumnComment. updateColumnComment
    fieldNames array The path to the field, as a list of field name segments. -
    newComment string The new field comment. col_comment_test

    UpdateColumnType

    Name Type Description Example
    - object Updates a column type. -
    type string Fixed value: updateColumnType. updateColumnType
    fieldNames array The path to the field, as a list of field name segments. -
    newDataType DataType The new field data type. -
    keepNullability boolean Whether to preserve the existing nullability setting when changing the type. true

    UpdateColumnPosition

    Name Type Description Example
    - object Updates the position of a column. -
    type string Fixed value: updateColumnPosition. updateColumnPosition
    fieldNames array The path to the field, as a list of field name segments. -
    move Move The target position for the field. -

    UpdateColumnNullability

    Name Type Description Example
    - object Updates the nullability of a column. -
    type string Fixed value: updateColumnNullability. updateColumnNullability
    newNullability boolean Whether the column accepts null values. true

    Move

    Specifies how to position a field when adding or moving a column.

    Name Type Description Example
    - object Column position information. -
    fieldName string The name of the field to move. col_test
    referenceFieldName string The reference field for AFTER and BEFORE positioning. other_col_test
    type string The move type. Valid values: FIRST, AFTER, BEFORE, LAST. FIRST