metric_id int(11) not_null auto_increment comment(Auto-incrementing metric ID)
objective_id varchar(36) not_null comment(Objective this metric belongs to)
metric_name varchar(100) not_null comment(Name of the metric (e.g., execution_time, accuracy))
metric_value decimal(10,4) not_null comment(Numeric value of the metric)
recorded_at timestamp NULL default(current_timestamp) comment(When the metric was recorded)

--
primary metric_id
idx_objective_id objective_id 
idx_metric_name metric_name 
idx_recorded_at recorded_at 
idx_objective_metric objective_id metric_name

##
engine innodb
character_set utf8mb4
collate utf8mb4_unicode_ci