Data Types

Note

This document has been machine translated.

column_def

Represents column information for a dataset. It is expressed as a JSON Object with the following fields:

• column_name (string): Column name.
• data_type (string): Data type.
• nullable (boolean): Nullability flag. If true, null values are allowed. If false, null values are not allowed and will result in an error. This field is optional in request data. If omitted, it defaults to false.
• attnum (integer): Column number in the database. This field may be deprecated in the future. Do not use it. This field cannot be specified in request data.

dataset_info

Represents dataset information. It is expressed as a JSON Object with the following fields:

• id (integer): ID in the internal management table. This field may be deprecated in the future. Do not use it.
• session_id (integer): Session ID. This field may be deprecated in the future. Do not use it.
• usename (string): Database role name. This field may be deprecated in the future. Do not use it.
• ddc_type (string): Type. This field may be deprecated in the future. Do not use it.
• short_form (string): Dataset name.
• long_form (string): Long-form dataset name. This field may be deprecated in the future. Do not use it.
• realname (string): Table name in the database. This field may be deprecated in the future. Do not use it.
• created_at (object): Dataset creation date and time. This field may be deprecated in the future. Do not use it.
• committed_at (object): Dataset commit date and time. This field may be deprecated in the future. Do not use it.
• prepared_activity_id (integer): Operation information for the dataset. This field may be deprecated in the future. Do not use it.

citation_info

Represents citation information. It is expressed as a JSON Object with the following fields:

• id (integer): ID in the internal management table. This field may be deprecated in the future. Do not use it.
• short_form (string): Citation name.
• long_form (string): Long-form citation name.
• dataset_name (string): Dataset name.
• dataset_realname (string): Table name of the dataset in the database. This field may be deprecated in the future. Do not use it.
• transaction_time (object): Citation issuance date and time.
• created_at (object): Citation creation date and time in the database. This field may be deprecated in the future. Do not use it.

upstream_info

Represents upstream information for the Model Store. It is expressed as a JSON Object with the following fields:

• id (integer): ID in the internal management table.
• model_store_ddc_id (string): Legacy Model Store ID in the internal management table. This field may be deprecated in the future. Do not use it.
• model_store_dataset_id (integer): Model Store ID in the internal management table. This field may be deprecated in the future. Do not use it.
• upstream_endpoint (string): Endpoint of the upstream node.
• upstream_apikey (string): API key for connecting to the upstream node.
• upstream_secret (string): Secret for connecting to the upstream node.
• upstream_model_store_ddc (string): Model Store name of the upstream node.
• alias (string): Alias name.
• description (string): Description.
• enabled (boolean): Flag indicating whether the entry is enabled or disabled.
• created_at (object): Creation date and time of the upstream information in the database. This field may be deprecated in the future. Do not use it.
• updated_at (object): Last update date and time of the upstream information in the database. This field may be deprecated in the future. Do not use it.

model_info

Represents model information. It is expressed as a JSON Object with the following fields:

• start_datetime (object): Start date and time represented by the model. This field may be deprecated in the future. Do not use it.
• end_datetime (object): End date and time represented by the model. This field may be deprecated in the future. Do not use it.
• location (string): Spatial range represented by the model. This field may be deprecated in the future. Do not use it.
• tenant_id (string): Tenant ID of the xData Edge instance where the model was generated.
• model_id (string): ID uniquely identifying the model.
• model_kind (string): Model type.
• model_description (string): Model description.
• model_meta (object): Model metadata.
• model_state (integer): Classification number representing the model state. Used to distinguish states within the federated learning cycle.
  • 10: Trained model.
  • 20: Model fed back from the downstream node.
  • 30: Aggregated model.
  • 40: Model transferred from the upstream node.
• model_hash (string): Hash value of the model.
• model_size (integer): Size of the model as binary data.
• round (integer): Round number in federated learning. Currently not used.
• hop_count (integer): Number of hops in model transfer between nodes. Currently not used.
• model_store_ddc (string): Name of the Model Store where this model is stored.

condition

Represents the conditions for retrieving various information such as dataset records. It is expressed using JSON Logic notation. However, the available operators differ from standard JSON Logic.

• https://jsonlogic.com/

Example

{
    "and": [
        { ">=": [ "age", 20 ] },
        { "<" : [ "age", 30 ] }
    ]
}

This example represents the condition "the value of the 'age' column is greater than or equal to 20 and less than 30".

Expression

A single condition expression is written as a JSON object as follows:

{
    "operator": [ "operand1", "operand2", ... ]
}

• The JSON object has exactly one key. The type of operation is determined by the key name.
• The value corresponding to the key is a JSON array. Each element in the array becomes a parameter (operand) of the operation. The number and type of parameters vary depending on the operator.

Column Name

Dataset column names are written as JSON strings.

Values

Literals such as numbers, strings, and booleans are written as JSON values. However, strings that match a dataset column name are interpreted as column names.

Operators

The following operators are available:

Operator	Description	Number of Parameters
=	A is equal to B	2
<>	A is not equal to B	2
>	A is greater than B	2
>=	A is greater than or equal to B	2
<	A is less than B	2
<=	A is less than or equal to B	2
!	Negation of the parameter	1
and	All parameters are true	Any
or	Any parameter is true	Any
in	A is equal to any element in B	2 (B is a JSON array)
+	Sum of all parameters	Any
*	Product of all parameters	Any
-	A - B	2
/	A / B	2