Question

I am attempting to copy data from specific columns in one row, and have it inserted/updated into another row, all in the same table. Each row already has an ID # (called order_no), so no auto-increment is needed.

I thought this would be pretty simple, but it’s just not working. my Table name is ‘orders’ and the columns are called ‘rn’ and ‘phone’ and the order_no are ‘416’ and ‘417’. I want rn, and phone from 416 to be inserted into the rn, and phone columns for 417.

I also have tried this query, attempting to copy just one record rn, with no success
and get error: #1248 – Every derived table must have its own alias

mysql_query("UPDATE orders
  SET rn =
     ( SELECT rn
        FROM ( SELECT rn
                FROM orders
                  WHERE order_no = 416
             ) 
 WHERE order_no = 417 ");

I have tried this with no success, and get Error #1136 – Column count doesn’t match value count at row 1

  mysql_query
(" INSERT INTO orders (rn, phone)
SELECT rn, phone, 416
from orders
WHERE order_no = 417 ");

Update. I also tried this query below, with just one field (rn) to no avail, and it throws error #1093 – You can’t specify target table ‘orders’ for update in FROM clause:

     mysql_query("UPDATE orders 
SET rn = (SELECT rn FROM orders WHERE order_no = '416') 
WHERE order_no = '417' ");

Any help or assistance is greatly appreciated. Thank you

Answer 1

You can modify your query

mysql_query
(" INSERT INTO orders (rn, phone)
SELECT rn, phone, 416
WHERE order_no = 417 ");

to

mysql_query
(" INSERT INTO orders (rn, phone)
SELECT rn, phone, 416
from orders
WHERE order_no = 417 ");