OpenMetadata/docs/openmetadata-apis/schemas/entities/table.md

Table

This schema defines the Table entity. A Table organizes data in rows and columns and is defined by a Schema. OpenMetadata does not have a separate abstraction for Schema. Both Table and Schema are captured in this entity.

**$id: **https://open-metadata.org/schema/entity/data/table.json

Type: object

Properties

• id required
  • Unique identifier of this table instance.
  • $ref: ../../type/basic.json#/definitions/uuid
• name required
  • Name of a table. Expected to be unique within a database.
  • $ref: #/definitions/tableName
• displayName
  • Display Name that identifies this table. It could be title or label from the source services.
  • Type: string
• fullyQualifiedName
  • Fully qualified name of a table in the form serviceName.databaseName.tableName.
  • Type: string
• description
  • Description of a table.
  • Type: string
• version
  • Metadata version of the entity.
  • $ref: ../../type/basic.json#/definitions/entityVersion
• updatedAt
  • Last update time corresponding to the new version of the entity.
  • $ref: ../../type/basic.json#/definitions/dateTime
• updatedBy
  • User who made the update.
  • Type: string
• href
  • Link to this table resource.
  • $ref: ../../type/basic.json#/definitions/href
• tableType
  • $ref: #/definitions/tableType
• columns required
  • Columns in this table.
  • Type: array
    • Items
    • $ref: #/definitions/column
• tableConstraints
  • Table constraints.
  • Type: array
    • Items
    • $ref: #/definitions/tableConstraint
• owner
  • Owner of this table.
  • $ref: ../../type/entityReference.json
• database
  • Reference to Database that contains this table.
  • $ref: ../../type/entityReference.json
• viewDefinition
  • View Definition in SQL. Applies to TableType.View only.
  • $ref: ../../type/basic.json#/definitions/sqlQuery
• tags
  • Tags for this table.
  • Type: array
    • Items
    • $ref: ../../type/tagLabel.json
• usageSummary
  • Latest usage information for this table.
  • $ref: ../../type/usageDetails.json
• followers
  • Followers of this table.
  • $ref: ../../type/entityReference.json#/definitions/entityReferenceList
• joins
  • Details of other tables this table is frequently joined with.
  • $ref: #/definitions/tableJoins
• sampleData
  • Sample data for a table.
  • $ref: #/definitions/tableData
• tableProfile
  • Data profile for a table.
  • Type: array
    • Items
    • $ref: #/definitions/tableProfile

Type definitions in this schema

tableType

• This schema defines the type used for describing different types of tables.
• Type: string
• The value is restricted to the following:
  1. "Regular"
  2. "External"
  3. "View"
  4. "SecureView"
  5. "MaterializedView"

dataType

• This enum defines the type of data stored in a column.
• Type: string
• The value is restricted to the following:
  1. "NUMBER"
  2. "TINYINT"
  3. "SMALLINT"
  4. "INT"
  5. "BIGINT"
  6. "BYTEINT"
  7. "FLOAT"
  8. "DOUBLE"
  9. "DECIMAL"
  10. "NUMERIC"
  11. "TIMESTAMP"
  12. "TIME"
  13. "DATE"
  14. "DATETIME"
  15. "INTERVAL"
  16. "STRING"
  17. "MEDIUMTEXT"
  18. "TEXT"
  19. "CHAR"
  20. "VARCHAR"
  21. "BOOLEAN"
  22. "BINARY"
  23. "VARBINARY"
  24. "ARRAY"
  25. "BLOB"
  26. "LONGBLOB"
  27. "MEDIUMBLOB"
  28. "MAP"
  29. "STRUCT"
  30. "UNION"
  31. "SET"
  32. "GEOGRAPHY"
  33. "ENUM"
  34. "JSON"

constraint

• This enum defines the type for column constraint.
• Type: string
• The value is restricted to the following:
  1. "NULL"
  2. "NOT_NULL"
  3. "UNIQUE"
  4. "PRIMARY_KEY"

tableConstraint

• This enum defines the type for table constraint.
• Type: object
• Properties
  • constraintType
    • Type: string
    • The value is restricted to the following:
      1. "UNIQUE"
      2. "PRIMARY_KEY"
      3. "FOREIGN_KEY"
  • columns
    • List of column names corresponding to the constraint.
    • Type: array
      • Items
      • Type: string

columnName

• Local name (not fully qualified name) of the column. ColumnName is - when the column is not named in struct dataType. For example, BigQuery supports struct with unnamed fields.
• Type: string
• The value must match this pattern: ^[^.]*$
• Length: between 1 and 64

tableName

• Local name (not fully qualified name) of a table.
• Type: string
• The value must match this pattern: ^[^.]*$
• Length: between 1 and 64

fullyQualifiedColumnName

• Fully qualified name of the column that includes serviceName.databaseName.tableName.columnName[.nestedColumnName]. When columnName is null for dataType struct fields, field_# where # is field index is used. For map dataType, for key the field name key is used and for the value field value is used.
• Type: string
• Length: between 1 and 256

column

• This schema defines the type for a column in a table.
• Type: object
• This schema does not accept additional properties.
• Properties
  • name required
    • $ref: #/definitions/columnName
  • dataType required
    • Data type of the column (int, date etc.).
    • $ref: #/definitions/dataType
  • arrayDataType
    • Data type used array in dataType. For example, array<int> has dataType as array and arrayDataType as int.
    • $ref: #/definitions/dataType
  • dataLength
    • Length of char, varchar, binary, varbinary dataTypes, else null. For example, varchar(20) has dataType as varchar and dataLength as 20.
    • Type: integer
  • dataTypeDisplay
    • Display name used for dataType. This is useful for complex types, such as `array, map<int,string>, struct<>, and union types.
    • Type: string
  • description
    • Description of the column.
    • Type: string
  • fullyQualifiedName
    • $ref: #/definitions/fullyQualifiedColumnName
  • tags
    • Tags associated with the column.
    • Type: array
      • Items
      • $ref: ../../type/tagLabel.json
  • constraint
    • Column level constraint.
    • $ref: #/definitions/constraint
  • ordinalPosition
    • Ordinal position of the column.
    • Type: integer
  • jsonSchema
    • Json schema only if the dataType is JSON else null.
    • Type: string
  • children
    • Child columns if dataType or arrayDataType is map, struct, or union else null.
    • Type: array
      • Items
      • $ref: #/definitions/column

columnJoins

• This schema defines the type to capture how frequently a column is joined with columns in the other tables.
• Type: object
• This schema does not accept additional properties.
• Properties
  • columnName
    • $ref: #/definitions/columnName
  • joinedWith
    • Fully qualified names of the columns that this column is joined with.
    • Type: array
      • Items
      • Type: object
      • Properties
        • fullyQualifiedName
          • $ref: #/definitions/fullyQualifiedColumnName
        • joinCount
          • Type: integer

tableJoins

• This schema defines the type to capture information about how columns in this table are joined with columns in the other tables.
• Type: object
• This schema does not accept additional properties.
• Properties
  • startDate
    • Date can be only from today going back to last 29 days.
    • $ref: ../../type/basic.json#/definitions/date
  • dayCount
    • Type: integer
    • Default: 1
  • columnJoins
    • Type: array
      • Items
      • $ref: #/definitions/columnJoins

tableData

• This schema defines the type to capture rows of sample data for a table.
• Type: object
• This schema does not accept additional properties.
• Properties
  • columns
    • List of local column names (not fully qualified column names) of the table.
    • Type: array
      • Items
      • $ref: #/definitions/columnName
    • rows
      • Data for multiple rows of the table.
      • Type: array
        • Items
        • Data for a single row of the table within the same order as columns fields.
        • Type: array

columnProfile

• This schema defines the type to capture the table's column profile.
• Type: object
• Properties
  • name
    • Column Name.
    • Type: string
  • uniqueCount
    • No. of unique values in the column.
    • Type: number
  • uniqueProportion
    • Proportion of number of unique values in a column.
    • Type: number
  • nullCount
    • No.of null values in a column.
    • Type: number
  • nullProportion
    • No.of null value proportion in columns.
    • Type: number
  • min
    • Minimum value in a column.
    • Type: string
  • max
    • Maximum value in a column.
    • Type: string
  • mean
    • Avg value in a column.
    • Type: string
  • median
    • Median value in a column.
    • Type: string
  • stddev
    • Standard deviation of a column.
    • Type: number

tableProfile

• This schema defines the type to capture the table's data profile.
• Type: object
• This schema does not accept additional properties.
• Properties
  • profileDate
    • Data one which profile is taken.
    • $ref: ../../type/basic.json#/definitions/date
  • columnCount
    • No.of columns in the table.
    • Type: number
  • rowCount
    • No.of rows in the table.
    • Type: number
  • columnProfile
    • List of local column profiles of the table.
    • Type: array
      • Items
      • $ref: #/definitions/columnProfile

This document was updated on: Monday, October 18, 2021