Basic Types¶

Fundamental type definitions used throughout OpenMetadata schemas.

Overview¶

Basic types are the building blocks for all OpenMetadata schemas. They provide standardized, reusable type definitions.

String Types¶

UUID¶

Definition: type/basic.json#/definitions/uuid

RFC 4122 compliant universally unique identifiers:

{
  "type": "string",
  "format": "uuid",
  "pattern": "^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$"
}

Usage: Entity IDs, references

Email¶

Definition: type/basic.json#/definitions/email

RFC 5322 email addresses:

{
  "type": "string",
  "format": "email",
  "pattern": "^[\\w\\.\\-]+@[\\w\\-]+\\.[\\w\\-\\.]+$"
}

Markdown¶

Definition: type/basic.json#/definitions/markdown

CommonMark formatted text for rich descriptions:

{
  "type": "string",
  "description": "Markdown formatted text"
}

URI¶

Definition: type/basic.json#/definitions/href

HTTP/HTTPS URIs:

{
  "type": "string",
  "format": "uri"
}

Temporal Types¶

Timestamp¶

Definition: type/basic.json#/definitions/timestamp

ISO 8601 timestamps:

{
  "type": "number",
  "description": "Unix epoch timestamp in milliseconds"
}

Example: 1704067200000 (2024-01-01T00:00:00Z)

Date¶

Definition: type/basic.json#/definitions/date

ISO 8601 dates:

{
  "type": "string",
  "format": "date",
  "pattern": "^\\d{4}-\\d{2}-\\d{2}$"
}

Example: "2024-01-01"

Time¶

Definition: type/basic.json#/definitions/time

ISO 8601 times:

{
  "type": "string",
  "format": "time"
}

Example: "14:30:00"

Duration¶

Definition: type/basic.json#/definitions/duration

ISO 8601 durations:

{
  "type": "string",
  "format": "duration"
}

Example: "P1DT12H30M" (1 day, 12 hours, 30 minutes)

Numeric Types¶

Integer¶

Standard JSON integer:

{
  "type": "integer"
}

Number¶

JSON number (float/double):

{
  "type": "number"
}

Boolean¶

Standard JSON boolean:

{
  "type": "boolean"
}

Expression Types¶

SQL Expression¶

Definition: type/basic.json#/definitions/sqlQuery

SQL query strings:

{
  "type": "string",
  "description": "SQL expression or query"
}

SQL Function¶

SQL function expressions:

{
  "type": "string",
  "description": "SQL function like COUNT(*), SUM(column)"
}

Entity Links¶

Entity Link¶

Definition: type/basic.json#/definitions/entityLink

Links to specific entities or entity fields:

<#E::table::db.schema.table>
<#E::table::db.schema.table::columns::column_name>

Format: <#E::{entityType}::{fqn}[::{field}::{fieldValue}]>

Enum Types¶

Style Enums¶

Constrained string values:

{
  "type": "string",
  "enum": ["Regular", "View", "MaterializedView", "Temporary"]
}

Validation Patterns¶

Name Pattern¶

Valid entity names:

{
  "type": "string",
  "minLength": 1,
  "maxLength": 256,
  "pattern": "^[a-zA-Z0-9_.-]+$"
}

FQN Pattern¶

Fully qualified names:

{
  "type": "string",
  "minLength": 1,
  "maxLength": 3072
}

Best Practices¶

Use Standard Types: Always reference basic types instead of redefining
Validation: Leverage format and pattern validations
Constraints: Add min/max length where appropriate
Documentation: Document custom constraints