class CQL::ForeignKey

• CQL::ForeignKey
• Reference
• Object

Overview

A foreign key constraint: the local columns, the referenced table and columns, and the ON DELETE / ON UPDATE actions. Declare one with Table#foreign_key in a table block, or add one later with AlterTable#foreign_key.

Example Declaring a foreign key

schema.table :comments do
  primary :id, Int64
  column :post_id, Int64
  foreign_key [:post_id], references: :posts, references_columns: [:id], on_delete: :cascade
end

Defined in:

Constructors

• .new(table : CQL::Table, columns : Array(Symbol), references_table : Symbol, references_columns : Array(Symbol), name : String | Nil = nil, on_delete : Symbol = :no_action, on_update : Symbol = :no_action)

Instance Method Summary

• #columns : Array(Symbol)

  The column(s) in the current table that make up the foreign key.

• #name : String | Nil

  Name of the foreign key constraint (optional, often auto-generated).

• #on_delete : Symbol

  Action to perform on delete (e.g., :cascade, :restrict, :set_null, :no_action).

• #on_update : Symbol

  Action to perform on update (e.g., :cascade, :restrict, :set_null, :no_action).

• #references_columns : Array(Symbol)

  The column(s) in the referenced table.

• #references_table : Symbol

  The table that the foreign key references.

• #table : CQL::Table

  The table this foreign key constraint belongs to.

Constructor Detail

Instance Method Detail