Appendix 1: Lists and structure details of metadata tables -

The data opening feature of DataWorks provides metadata tables in various dimensions for you to collect metadata. This topic provides lists of such tables and describes the structure details of these tables.

Note

Unless otherwise specified, the metadata provided by the data opening feature includes only the metadata of the MaxCompute compute engine.

Metadata
- RPT metrics
  - Core table metrics: rpt_v_meta_ind_table_core
  - Additional table metrics: rpt_v_meta_ind_table_extra
- Raw metadata details
Scheduling-related metadata
Tenant metadata

Core table metrics: rpt_v_meta_ind_table_core

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The DataWorks workspace ID.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_name	string	The name of the table.
table_uuid	string	The table ID.
owner_yun_acct	string	The Alibaba Cloud account of the table owner.
dim_life_cycle	bigint	The time to live (TTL). Unit: days. Valid values: 0: indicates that no TTL is configured. Other values: indicate a specific period of time.
is_partition_table	boolean	Specifies whether the table is a partitioned table. Valid values: true: The table is a partitioned table. false: The table has no partitions.
entity_type	bigint	The type of the entity. Valid values: 0: table 1: view
categories	string	The category information.
last_access_time	bigint	The time when the table was last accessed. The value is a 10-digit UNIX timestamp.
size	bigint	The size of the table, which indicates the logical storage space occupied by data in the table. Unit: bytes. This field is set to NULL for a view.
column_count	bigint	The number of fields in the table. Partition key columns are included.
partition_count	bigint	The number of partitions in the table. This field is set to NULL for a non-partitioned table.
detail_view_count	bigint	The number of times that table details are viewed on the page.
favorite_count	bigint	The number of times that the table is added to favorites.

Additional table metrics: rpt_v_meta_ind_table_extra

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
table_uuid	string	The table ID.
read_count	bigint	The number of times that data is read using SQL statements. The data includes that of non-scheduled tasks.
read_count_30d	bigint	The number of times that data is read within 30 days using SQL statements. The data includes that of non-scheduled tasks.
write_count	bigint	The number of times that data is written using SQL statements. The data includes that of non-scheduled tasks.
join_count	bigint	The number of times that the table is joined.
direct_upstream_count	bigint	The number of parent tables in the lineage.
direct_downstream_count	bigint	The number of child tables in the lineage.
output_task_count	bigint	The number of tasks that generate the data in the table.

Database (MaxCompute project) metadata details: raw_v_meta_database

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The DataWorks workspace ID.
env_type	bigint	The environment type. Valid values: 0: development environment 1: production environment
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
database_comment	string	The description of the database or MaxCompute project.
owner_name	string	The name of the owner.
created_time_ts	bigint	The creation time. The value is a 13-digit timestamp.
last_modified_time_ts	bigint	The last modification time. The value is a 13-digit timestamp.
location	string	The storage path of the database.
extras	string	The additional information about the database, which is a JSON string. If the table preview and table visibility range attributes are configured for a MaxCompute project, you can use the allowDataPreview and projectVisibility keys to obtain the values of the attributes. allowDataPreview: specifies whether tables in a MaxCompute project can be previewed. Valid values: true: The operation is allowed. Other values or NULL: Tables in a MaxCompute project cannot be previewed. projectVisibility: specifies the visibility range of tables in a MaxCompute project. Valid values: 0: hidden. Tables are visible only for table owners, project administrators, and project owners. 1: visible for all users within the tenant. 2: visible for project members.
biz_date	string	The data timestamp.

Table metadata details: raw_v_meta_table

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	string	The DataWorks workspace ID.
table_uuid	string	The table ID.
table_name	string	The name of the table.
table_type	string	The type of the table.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
partition_keys	string	The partition keys in the table. Multi-level partition keys are separated by commas (,). This field is set to an empty string for a non-partitioned table.
table_comment	string	The description of the table.
table_biz_comment	string	The business description of the table.
visibility_scope	bigint	The visibility range of the table. 0: hidden. Tables are visible only for table owners, project administrators, and project owners. 1: visible for all users within the tenant. 2: visible for project members.
owner_name	string	The name of the owner.
created_time_ts	bigint	The creation time. The value is a 13-digit timestamp.
last_modified_time_ts	bigint	The time when data was last modified. The value is a 13-digit timestamp.
last_meta_modified_time_ts	bigint	The time when table metadata was last modified. The value is a 13-digit timestamp.
location	string	The storage path of the table.
life_cycle	bigint	The TTL of the table. Unit: days.
data_size	bigint	The logical storage volume of the table. Unit: bytes. If the table is a partitioned table, this field is set to NULL. You must collect statistics on the storage volume based on the partition list.
biz_date	string	The data timestamp.

View metadata details: raw_v_meta_view

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	string	The DataWorks workspace ID.
table_uuid	string	The table ID.
table_name	string	The name of the table.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_comment	string	The description of the table.
table_biz_comment	string	The business description of the table.
visibility_scope	bigint	The visibility range of the table. 0: hidden. Tables are visible only for table owners, project administrators, and project owners. 1: visible for all users within the tenant. 2: visible for project members.
owner_name	string	The name of the owner.
created_time_ts	bigint	The creation time. The value is a 13-digit timestamp.
last_ddl_time_ts	bigint	The time when the DDL statement of the view was last modified. The value is a 13-digit timestamp.
view_text	string	The SQL statement that is used to create a view.
biz_date	string	The data timestamp.

Column metadata details: raw_v_meta_column

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The DataWorks workspace ID.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_name	string	The name of the table.
column_name	string	The name of the field.
column_comment	string	The description of the field.
column_biz_comment	string	The business description of the field.
column_type	string	The data type of the field.
column_sequence	bigint	The sequence number of the field, which starts from 1.
is_partition_key	boolean	Specifies whether the field is a partition key.
is_primary_key	boolean	Specifies whether the field is a primary key.
biz_date	string	The data timestamp.

Partition metadata details: raw_v_meta_partition

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The DataWorks workspace ID.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_name	string	The name of the table.
partition_name	string	The name of the partition.
size	bigint	The logical size of the partition. Unit: bytes.
record_number	bigint	The number of records in the partition.
created_time_ts	bigint	The creation time. The value is a 13-digit timestamp.
last_modified_time_ts	bigint	The last modification time. The value is a 13-digit timestamp.
biz_date	string	The data timestamp.

Table lineage metadata details: raw_v_meta_table_lineage

Note

The lineage feature cannot achieve 100% data integrity and accuracy due to the complexity of SQL statements and code. We recommend that you do not use this feature for the business that has integrity and accuracy requirements.
The table lineage data includes the lineage relationships generated by the MaxCompute compute engine and the lineage relationships generated by batch synchronization tasks.

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The DataWorks workspace ID.
src_type	string	The type of the source.
src_data_source_id	string	The source ID.
src_database	string	The source database.
src_table	string	The source table.
dest_type	string	Target Data Source
dest_data_source_id	string	The destination ID.
dest_database	string	The destination database.
dest_table	string	The destination table.
schedule_task_id	string	The scheduled task ID.
schedule_instance_id	string	The instance ID of the scheduled task.
schedule_task_owner	string	The owner of the scheduled task.
job_start_time_ts	bigint	The start time of the task, which is a 13-digit timestamp.
job_end_time_ts	bigint	The end time of the task, which is a 13-digit timestamp.
execute_time	bigint	The time that is consumed to run the task. Unit: seconds.
input_record_number	bigint	The number of records that are read from the source table.
biz_date	string	The data timestamp.

Table output task metadata details: raw_v_meta_table_output

Data Map displays only the tables whose data is generated by ODPS nodes. The metadata includes the tables whose data is generated by ODPS nodes and Data Integration nodes.

Note

The output information is generated based on lineage.

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The ID of the DataWorks workspace in which scheduled tasks are run.
type	string	The type of the data source.
data_source_id	string	The data source ID.
database	string	The database.
table	string	The name of the table.
schedule_task_id	string	The scheduled task ID.
schedule_instance_id	string	The instance ID of the scheduled task.
schedule_task_owner	string	The owner of the scheduled task.
job_start_time_ts	bigint	The start time of the task, which is a 13-digit timestamp.
job_end_time_ts	bigint	The end time of the task, which is a 13-digit timestamp.
execute_time	bigint	The time that is consumed to run the task. Unit: seconds.
biz_date	string	The data timestamp.

Table usage metadata details: raw_v_meta_table_usage

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The ID of the DataWorks workspace in which scheduled tasks are run.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_name	string	The name of the table.
schedule_task_id	string	The scheduled task ID.
schedule_task_owner	string	The owner of the scheduled task. If the current task is not scheduled in DataWorks, this field is set to NULL.
job_id	string	The task ID, which may not be the instance ID of the task that is scheduled in DataWorks. You can use this field to count the number of times that data is read from the table and the number of times that data is written to the table.
op_type	string	The operation type, which can be READ, WRITE, or UNKNOWN.
extras	string	The additional information, which is a JSON string. If a MaxCompute task performs operations on the table, you can use the `task_name` key to get the name of the MaxCompute task. If the ID of a DataWorks scheduled task is not empty, you can use the `schedule_task_name` attribute to get the name of the scheduled task. For example: `{ "task_name": "console_query_task_16056294000000", "schedule_task_name": "Test SQL task" }`.
biz_date	string	The data timestamp.

Column usage metadata details: raw_v_meta_column_usage

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The ID of the DataWorks workspace in which scheduled tasks are run.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_name	string	The name of the table.
column_name	string	The name of the field.
schedule_task_id	string	The scheduled task ID.
schedule_task_owner	string	The owner of the scheduled task. If the current task is not scheduled in DataWorks, this field is set to NULL.
inst_id	string	The task ID, which may not be the instance ID of the task that is scheduled in DataWorks.
op_type	string	The operation type, which can be SELECT, JOIN, GROUP BY, or WHERE.
extras	string	The additional information, which is a JSON string. If a MaxCompute task performs operations on the table, you can use the `task_name` key to get the name of the MaxCompute task. If the ID of a DataWorks scheduled task is not empty, you can use the `schedule_task_name` attribute to get the name of the scheduled task. For example: `{ "task_name": "console_query_task_16056294000000", "schedule_task_name": "Test SQL task" }`.
biz_date	string	The data timestamp.

Table Wiki metadata details: raw_v_meta_biz_table_wiki

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The ID of the DataWorks workspace in which scheduled tasks are run.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_name	string	The name of the table.
version	string	The version number of Wiki.
operator	string	The final operator, which may be an owner of the table.
content	string	The content of Wiki, which is written using the Markdown syntax.
update_time_ts	bigint	The modification time. The value is a 13-digit timestamp.
biz_date	string	The data timestamp.

Table join metadata details: raw_v_meta_table_join_map

Field name	Type	Description
tenant_id	bigint	The DataWorks tenant ID.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_name	string	The name of the table.
column_name	string	The name of the field.
join_database_name	string	The name of the associated database or MaxCompute project.
join_table_name	string	The name of the associated table.
join_column_name	string	The name of the associated field.
join_type	string	The type of the JOIN operation, which can be left, right, or inner.
schedule_task_id	string	The scheduled task ID.
schedule_task_owner	string	The owner of the scheduled task.
job_id	string	The ID of the task at the engine layer.
extras	string	The additional information, which is a JSON string. If a MaxCompute task is run to perform operations on a table, you can use the task_name key to obtain the name of the MaxCompute task.
biz_date	string	The data timestamp.

Table viewing records: raw_v_meta_table_detail_log

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
catalog_name	string	The name of the catalog. This field is set to odps for MaxCompute projects.
database_name	string	The name of the database or MaxCompute project.
table_name	string	The name of the table.
operator	string	The user who views table details.
view_time_ts	bigint	The time when table details are viewed. The value is a 13-digit timestamp.
biz_date	string	The data timestamp.

Category metadata details: raw_v_meta_category

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
category_id	bigint	The category ID.
category_name	string	The name of the category.
category_pid	bigint	The parent category ID. This field is set to 0 or NULL for a level-1 category.
depth	bigint	The level of the category. This field is set to 1 for a level-1 category.
sort_field	double	The field based on which the categories are sorted.
creator_account	string	The account that is used to create the category.
created_time_ts	bigint	The creation time. The value is a 13-digit timestamp.
last_modified_time_ts	bigint	The last modification time. The value is a 13-digit timestamp.
biz_date	string	The data timestamp.

Scheduling node details: raw_v_schedule_node

Field name	Data type	Description
tenant_id	bigint	The tenant ID.
project_id	bigint	The workspace ID.
node_id	bigint	The node ID.
node_name	string	The name of the node.
node_type	bigint	The scheduling type of the node. Valid values: 0: Recurring schedule. 1: manually triggered node 2. Pausing a Job 3: dry-run node
prg_type	bigint	The type of the node. For more information, see Supported node types. 10: ODPS SQL node 23: Data Integration node
flow_id	bigint	The workflow ID.
project_env	string	The identity of the environment. PROD: production environment DEV: development environment
create_time	bigint	The creation time. The value is a 13-digit timestamp.
create_user	string	The creator.
modify_time	bigint	The last modification time. The value is a 13-digit timestamp.
modify_user	string	The modifier.
prg_name	string	The name of the node type.
para_value	string	The execution parameter.
file_id	bigint	The ID of the file that corresponds to the node.
file_version	bigint	The version of the file that corresponds to the node.
owner	string	The owner of the node.
resgroup_id	bigint	The resource group ID.
baseline_id	bigint	The baseline ID.
cycle_type	bigint	Scheduling epoch. 0: daily, weekly, or monthly Other values: hourly or minutely
repeatable	bigint	Rerun ID 0: The node can be rerun only after it fails to run. 1: The node can be rerun regardless of whether the node is successfully run or fails to run. 2: The node cannot be rerun regardless of whether the node is successfully run or fails to run.
connection	string	The connection string of the data source.
dqc_type	bigint	DQC Type 0: The node is associated with a monitoring rule in Data Quality. 1: The node is not associated with a monitoring rule in Data Quality.
dqc_description	string	DQC rule expression
task_rerun_time	bigint	The number of times that the task can be rerun.
task_rerun_interval	bigint	The rerun interval. Unit: milliseconds.
cron_express	string	The CRON expression that specifies the scheduling frequency of the node.
priority	bigint	The priority of the task. Valid values: 1, 3, 5, 7, and 8. A larger value indicates a higher priority.
start_effect_date	bigint	The time when the node takes effect. The value is a 13-digit timestamp.
end_effect_date	bigint	The time when the node loses effect. The value is a 13-digit timestamp.
biz_date	string	The data timestamp.

Scheduling task details: raw_v_schedule_task

Field name	Data type	Description
tenant_id	bigint	The tenant ID.
project_id	bigint	The workspace ID.
node_id	bigint	The node ID.
node_name	string	The name of the node.
task_id	bigint	The name of the task.
dag_id	bigint	The directed acyclic graph (DAG) ID of the workflow.
task_type	bigint	The scheduling type of the task. Valid values: 0: auto triggered task 1: manually triggered task 2: paused task 3 or 5: dry-run task
dag_type	bigint	The type of the DAG. Valid values: 0: epoch 1: DAG for a manually triggered task 3: DAG for a data backfill task
prg_type	bigint	The type of the node. For more information, see Supported node types. 10: ODPS SQL node 23: Data Integration node
flow_id	bigint	The workflow ID.
create_time	bigint	The creation time. The value is a 13-digit timestamp.
modify_time	bigint	The last modification time. The value is a 13-digit timestamp.
cycle_time	bigint	The scheduling time, which is a 13-digit timestamp.
in_group_id	bigint	The serial number of the task.
prg_name	string	The name of the node type.
para_value	string	The execution parameter.
file_id	bigint	The ID of the file that corresponds to the task.
file_version	bigint	The version of the file that corresponds to the task.
owner	string	The owner of the node.
resgroup_id	bigint	The resource group ID.
baseline_id	bigint	The baseline ID.
cycle_type	bigint	The scheduling cycle. Valid values: 0: daily, weekly, or monthly Other values: hourly or minutely
repeatable	bigint	The rerun ID. 0: The node can be rerun only after it fails to run. 1: The node can be rerun regardless of whether the node is successfully run or fails to run. 2: The node cannot be rerun regardless of whether the node is successfully run or fails to run.
connection	string	The connection string of the data source.
dqc_type	bigint	DQC Type 0: The node is associated with a monitoring rule in Data Quality. 1: The node is not associated with a monitoring rule in Data Quality.
dqc_description	string	DQC Rule String
task_rerun_time	bigint	The number of times that the task can be rerun.
task_rerun_interval	bigint	The rerun interval. Unit: milliseconds.
begin_waittime_time	bigint	The time when the task starts to wait for the scheduling time to arrive. The value is a 13-digit timestamp.
finish_time	bigint	The time when the task finishes running. The value is a 13-digit timestamp.
begin_waitres_time	bigint	The time when the task starts to wait for resources. The value is a 13-digit timestamp.
begin_run_time	bigint	The time when the task starts to run. The value is a 13-digit timestamp.
rerun_times	bigint	The number of times that the task is rerun.
priority	bigint	The priority of the task. Valid values: 1, 3, 5, 7, and 8. A larger value indicates a higher priority.
task_key	string	The unique identifier of the task.
error_msg	string	The reason why the task fails to run.
status	bigint	The status of the task. Valid values: NOT_RUN(1, "Not all ancestor instances are successfully run.") WAIT_TIME(2, "The task is waiting for the scheduling time that is specified by dueTime or cycleTime to arrive.") WAIT_RESOURCE(3, "The task is delivered to the execution engine Alisa and is waiting for scheduling in a queue.") RUNNING(4, "running") CHECKING(7, "The task is run using Alisa, and data is delivered to Data Quality for verification.") CHECKING_CONDITION(8, "The task is run using Alisa, and branch conditions are being checked.") FAILURE(5, "The task fails to run.") SUCCESS(6, "Operation successful")
biz_date	string	The data timestamp.

Scheduling node relationships: raw_v_schedule_node_relation

Field name	Data type	Description
tenant_id	bigint	The tenant ID.
child_node_id	bigint	The descendant node ID.
parent_node_id	bigint	The ancestor node ID.
step_type	bigint	The dependency type. Valid values: 0: common 3: cross-cycle
child_flow_id	bigint	The workflow ID.
project_env	string	Environment Identity PROD: production environment DEV: development environment
create_time	bigint	The creation time. The value is a 13-digit timestamp.
create_user	string	The creator.
modify_time	bigint	The last modification time. The value is a 13-digit timestamp.
modify_user	string	The modifier.
biz_date	string	The data timestamp.

Relationships between instances of the scheduling task: raw_v_schedule_task_relation

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
child_task_id	bigint	The instance ID of the downstream task.
parent_task_id	bigint	The instance ID of the upstream task.
child_project_id	bigint	The ID of the workspace to which the instance of the downstream task belongs.
parent_project_id	bigint	The ID of the workspace to which the instance of the upstream task belongs.
step_type	bigint	The dependency type. 0: same-cycle 3: cross-cycle
daily_dag_id	bigint	The ID of the global DAG.
child_dag_inst_id	bigint	The ID of the local DAG.
biz_date	string	The data timestamp.

Resource group for Data Integration details: raw_v_schedule_di_resgroup

Field name	Data type	Description
tenant_id	bigint	The tenant ID.
project_id	bigint	The workspace ID.
node_id	bigint	The node ID.
project_env	string	The environment of the workspace.
res_group_identifier	string	The ID of the resource group for Data Integration.
src_type	string	The type of the source.
dst_type	string	The type of the destination.
src_datasource	string	The source.
dst_datasource	string	The destination.
config_concurrent	bigint	The number of parallel threads.
biz_date	string	The data timestamp.

Information about resource groups in a tenant (including resource groups for scheduling, resource groups for Data Integration, and MaxCompute quota groups): raw_v_tenant_res_group

Field name	Data type	Description
tenant_id	bigint	The tenant ID.
res_group_id	bigint	The resource group ID.
res_group_identifier	string	The identifier of the resource group.
res_group_type	bigint	The type of the resource group. Valid values: 1: resource group for scheduling 2: MaxCompute quota group 4: resource group for Data Integration
res_group_mode	bigint	Resource Group Type 1: subscription 2: pay-as-you-go 3: Developer Edition (available only for MaxCompute)
status	bigint	The status of the resource group. Valid values: 0: The resource group is normal. 1: Freeze 2. Delete 3: The resource group is being created. 4: The resource group fails to be created. 5: The resource group is being updated. 6: The resource group fails to be updated. 7: The resource group is being deleted. 8: The resource group fails to be deleted.
biz_ext_key	string	The extension field of the resource group. The value single indicates an exclusive resource group.
biz_date	string	The data timestamp.

Information about users in a tenant: raw_v_tenant_user

Field name	Data type	Description
tenant_id	bigint	The tenant ID.
yun_account	string	The Alibaba Cloud account.
account_name	string	The name of the account.
nick	string	The display name of the account.
full_yun_account	string	The Alibaba Cloud account that contains the account provider information.
biz_date	string	The data timestamp.

Information about workspaces in a tenant: raw_v_tenant_workspace

Field name	Data type	Description
tenant_id	bigint	The tenant ID.
project_id	bigint	The workspace ID.
project_name	string	The name of the workspace.
project_identifier	string	The identifier of the workspace.
project_desc	string	The description of the workspace.
project_owner	string	The owner of the workspace.
status	bigint	The status of the workspace. Valid values: 0: The workspace is normal. 1: The workspace is deleted. 2: The workspace is being initialized. 3: The workspace fails to be initialized. 4: The workspace is manually disabled. 5: The workspace is being deleted. 6: The workspace fails to be deleted. 7: The workspace is frozen due to overdue payments.
biz_date	string	The data timestamp.

Information about users in a workspace in a tenant: raw_v_tenant_workspace_user

Field name	Data type	Description
tenant_id	bigint	The DataWorks tenant ID.
project_id	bigint	The DataWorks workspace ID.
base_id	string	The base ID of the user.
status	bigint	The status of the user. Valid values: 0: The user is normal. 1: The user is disabled. 2: The user is deleted.
gmt_create_ts	bigint	The creation time. The value is a 13-digit timestamp.
gmt_modified_ts	bigint	The modification time. The value is a 13-digit timestamp.
biz_date	string	The data timestamp.