mysql - 如何在具有多个值的不同数据库中的 2 个表/不同列之间移动数据

Question

INSERT INTO a2.cat (id, img) SELECT category_id, category_id FROM topshop.category;

我需要在 category_-id 的列 img 中插入加值

INSERT INTO a2.cat (id, 'c'+img+'.jpg') SELECT category_id, category_id FROM topshop.category;

Answer 1

这里是：

INSERT INTO a2.cat 
  (id, img) 
SELECT 
  category_id, CONCAT('c',category_id,'.jpg')
FROM topshop.category;