database.orm.mixin.Mappable Class

Namespace: database.orm.mixin

Provide attributes for defining how subclasses map to relational database tables

Since R2023b

Description

database.orm.mixin.Mappable is an abstract class that provides attributes for defining how subclasses are mapped to relational database tables. Methods such as ormread, ormwrite, and ormupdate use these attributes to read and write objects directly to and from databases.

Class Attributes

`Abstract`	`true`
`HandleCompatible`	`true`

For information on class attributes, see Class Attributes.

Methods

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Public Methods

rowfilter

Return an unconstrained rowfilter object for filtering by the objects' properties

More About

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`Mappable` Class Attributes

These class attributes are specific to Mappable subclasses.

`TableName`	Defines the name of the corresponding table on the database.
`Catalog`	Defines the catalog where the corresponding table resides.
`Schema`	Defines the schema where the corresponding table resides.

Standard attributes also apply to Mappable subclasses. For details, see Class Attributes.

`Mappable` Property Attributes

These property attributes are specific to Mappable subclasses.

`ExcludeFromDatabase`	If true, identifies a property that should not be saved as a database column.
`PrimaryKey`	If true, the associated column is a part of the table's primary key. Requires `ExcludeFromDatabase` to be false. At least one property must have the `PrimaryKey` property.
`ColumnName`	Defines the name of the associated column on the database table.
`ColumnType`	Defines the type of the associated column on the database table.
`AutoIncrement` (since R2024a)	If true and if the data type is integer: The database automatically creates values for the `PrimaryKey` property when you insert the property with the `ormwrite` method. Requires `PrimaryKey` to be true. The `ormwrite` method creates a table definition with an autoincrementing primary key column. Supported databases include: PostgreSQL MySQL^® MariaDB^® SQLite Microsoft^® SQL Server^® Microsoft Access^® Oracle^®
`ForeignKey` (since R2024b)	If true, indicates that the property represents a foreign key relationship between the referencing class and the referenced class. Limitations include: The property must be a subclass of `database.orm.mixin.Mappable`. The value of the property must be scalar.
`LinkTables` (since R2024b)	If true, the property represents a link table on the database enforcing a many-to-many relationship between two classes. Limitations include: The property class must be a subclass of `database.orm.mixin.Mappable`. Values of the property can be vectors, scalars, or empty.

Standard attributes also apply to Mappable subclasses. For details, see Property Attributes.

Version History

Introduced in R2023b

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R2024b: Support ORM class mappings with `Mappable` attributes

You can now use link tables or foreign keys to specify relationships between ORM classes.

R2024a: Insert ORM objects with autoincrementing primary keys

You can now use autoincrementing primary keys by setting the Autoincrement property attribute.

database.orm.mixin.Mappable Class

Description

Class Attributes

Methods

Public Methods

More About

Mappable Class Attributes

Mappable Property Attributes

Version History

R2024b: Support ORM class mappings with Mappable attributes

R2024a: Insert ORM objects with autoincrementing primary keys

See Also

`Mappable` Class Attributes

`Mappable` Property Attributes

R2024b: Support ORM class mappings with `Mappable` attributes