extend_usages

Column Name	Type	Comment	Default	Null	Remark
id	bigint UNSIGNED	Primary Key ID		NO	Auto Increment
usage_type	tinyint UNSIGNED	Type of target		NO
usage_id	bigint UNSIGNED	Target primary key ID		NO
extend_id	bigint UNSIGNED	Extend Content ID		NO	Related field `extends->id`
can_delete	tinyint UNSIGNED	Can be deleted	1	NO	0. No / 1. Yes Editor: User has the right to delete
rating	smallint UNSIGNED	Display order	9	NO	Ascending order
plugin_fskey	varchar(64)	Related plugin		NO	Related field `extends->plugin_fskey`
created_at	timestamp	Create Time	CURRENT_TIMESTAMP	NO
updated_at	timestamp	Update Time		YES
deleted_at	timestamp	Delete Time		YES

Introduction to using target associations