如何用另一个表的关系更新列值

Question

How to add sub_cat_list.child_id dynamically from main_cat_list.id using php. below are 2 images of my parent and child table

How to add values into sub_cat_list.child_id relative to sub_cat_list=rel_main_cat using php

Answer 1

Why do you want to use php? It is possible with one query(if I correctly understood your question).

UPDATE sub_cat_list sub
 INNER JOIN main_cat_list main ON main.main_cat_name = sub.rel_main_cat
   SET child_id = main.id