CREATE TABLE primary_table (
  id bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  user_id bigint(20) unsigned NOT NULL,
  PRIMARY KEY (id)
);

CREATE TABLE join_table (
  id bigint(20) unsigned NOT NULL AUTO_INCREMENT,
  primary_table_id bigint(20) unsigned NOT NULL,
  other_table_id bigint(20) unsigned NOT NULL,
  is_active tinyint(1) NOT NULL DEFAULT '0',
  PRIMARY KEY (id)
);