JSON Schema

The root object of a Metadata.JSON object contains the following fields.

Field	Type	Description
path	String	Path to the dataset.
tables	List[Table]	Tables that compose this dataset.
foreign_keys	List[ForeignKey]	Reletionships between the tables of this dataset.
constraints	List[Constraint]	Constraints of this dataset.

Tables

The Table object contains the following fields.

Field	Type	Description
id	String	Unique id for the table.
path	String	Path to the CSV file containing the table.
name	String	Name of the table.
primary_key	String or List[String]	Name of the column (or list of columns) that compose the primary key of the table.
time_index	String	Name of the time index column.
headers	Boolean	Whether the CSV file indicated by path contains a header row.
number_of_rows	Integer	Number of rows in the table.
fields	List[Field]
system	String	System to which this table belongs.
application	String	Application to which this table belongs.

Each field in the Table object is specified by a dictionary containing:

Field	Type	Description
name	String	Name of the field.
data_type	String	Data type of the field.
data_subtype	String	Data subtype of the field.

Data Types

The data_type and data_subtype fields can take on the following values:

• categorical

  • subtypes: categorical, ordinal, boolean

• text

• numerical

  • subtypes: integer, float

• datetime

• id

• other

Foreign Keys

The ForeignKey object represents a relation between two tables and contains the following fields.

Field	Type	Description
table	String	Id of the child table.
field	String or List[STring]	Name of the column (or list of columns) from the child table that form this relationship.
ref_table	String	Id of the parent table.
ref_field	String or List[STring]	Name of the column (or list of columns) from the parent table that form this relationship.

Constraints

The Constraint object contains the following fields.

Field	Type	Description
constraint_type	String	Type of Constraint.
fields_under_consideration	List[ConstraintField]	Name of the fields of interest.
related_fields	List[ConstraintField]	Name of the fields that contribute to the field(s) of interest.

Each field in the Contraint object is specified by a dictionary containing:

Field	Type	Description
table	String	Id of the table to which the field belongs.
field	String	Name of the field.