下面的表格是最简单的形式。
表“pro\u details\u old”

+------+------------+--------+------------+
|  id  | project_no | amount |  pro_date  |
+------+------------+--------+------------+
| 1000 | 001/001    |  50000 | 2018-10-01 |
| 1001 | 001/002    |  25000 | 2018-10-06 |
| 1002 | 002/004    |  75000 | 2018-10-12 |
| 1003 | 002/005    |  65000 | 2018-09-22 |
| 1004 | 002/006    |  10000 | 2018-08-17 |
| 1005 | 003/002    |  12000 | 2018-10-08 |
| 1006 | 003/003    | 145000 | 2018-07-01 |
+------+------------+--------+------------+

表“pro\u details\u new”

+------+------------+--------+----------+
|  id  | project_no | amount | pro_date |
+------+------------+--------+----------+
| 1050 | 001/001    |  50000 |          |
| 1051 | 001/002    |  25000 |          |
| 1052 | 002/004    |  75000 |          |
| 1053 | 002/005    |  65000 |          |
| 1054 | 002/006    |  10000 |          |
| 1055 | 003/002    |  12000 |          |
| 1056 | 003/003    | 145000 |          |
+------+------------+--------+----------+

02）因此，我需要更新“问题”表中的“发布日期”列，同时比较上述02个表中的项目编号。已插入“问题”表的参考号和金额列。预期产出如下。

+----+--------+--------+-------------+
| id | ref_no | amount | issued_date |
+----+--------+--------+-------------+
|  1 |   1050 |  50000 | 2018-10-01  |
|  2 |   1051 |  25000 | 2018-10-06  |
|  3 |   1052 |  75000 | 2018-10-12  |
|  4 |   1053 |  65000 | 2018-09-22  |
|  5 |   1054 |  10000 | 2018-08-17  |
|  6 |   1055 |  12000 | 2018-10-08  |
|  7 |   1056 | 145000 | 2018-07-01  |
+----+--------+--------+-------------+

03）我使用了以下查询。

insert into issues 
set issued_date = 
      (select pro_date 
       from pro_details_old 
       where 
          pro_details_old.project_no = pro_details_new.project_no) 
       left join pro_details_new on pro_details_new.id = issues.ref_no

04）我不明白什么是错误的观点。有人能帮我吗？