Foreign Key Syntax and Keywords

This reference describes the syntax and keywords that apply to a foreign key, which you can define within persistent classes. Keywords (also known as class attributes) generally affect the compiler.

See “Foreign Key Definitions” for links to general information on defining foreign keys.

See the Table of Contents for a complete list of structures and keywords that apply to specific class members.

• Syntax of Foreign Keys in Class Definitions – Describes the structure of a foreign key definition. See Foreign Key Definitions for links to general information on defining foreign keys.
• Internal – Specifies whether this foreign key definition is internal (not displayed in the class documentation).
• NoCheck – Specifies whether InterSystems IRIS should check this foreign key constraint.
• OnDelete – Specifies the action that this foreign key should cause in the current table when a record deleted in the foreign table is referenced by a record in the current table.
• OnUpdate – Specifies the action that this foreign key should cause in the current table when the key value of a record in the foreign table is updated and that record is referenced by a record in the current table.
• SqlName – Specifies an SQL alias for the foreign key.