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Define a foreign key column

Source: R/Column.R
ForeignKey.Rd

Define a foreign key column

Usage

ForeignKey(
  type,
  ref_table = NULL,
  ref_column = NULL,
  references = NULL,
  on_delete = NULL,
  on_update = NULL,
  ...
)

Arguments

type

SQL data type (e.g. "INTEGER")

ref_table

Character. Name of the referenced table.

ref_column

Character. Name of the referenced column. Used when specifying the pieces separately.

references

"table.column" string specifying the referenced field. This is the recommended way to declare the target.

on_delete

Optional ON DELETE behavior (e.g. "CASCADE")

on_update

Optional ON UPDATE behavior

...

Reserved for extras like CHECK, COLLATE, etc.

Value

A ForeignKey object

Details

This function creates a ForeignKey object, which is a special type of Column. It inherits all properties of a Column and adds foreign key specific attributes. See Column for details on additional parameters that can be passed via ....

See also

Column

Examples

# Define a foreign key referencing the 'id' column in the 'users' table
user_id_fk <- ForeignKey("INTEGER", references = "users.id", on_delete = "CASCADE")

# Define a nullable foreign key with custom update behavior
category_id_fk <- ForeignKey(
  "INTEGER", references = "categories.id",
  nullable = TRUE, on_update = "SET NULL"
)