WARNING: This post will make you hungry.
I found myself wanting to select multiple, individual rows—instead of a group—and concatenate on a certain field.
Let's say you have a table of product ids and their names and prices:
+------------+--------------------+-------+
| product_id | name | price |
+------------+--------------------+-------+
| 13 | Double Double | 5 |
| 14 | Neapolitan Shake | 2 |
| 15 | Animal Style Fries | 3 |
| 16 | Root Beer | 2 |
| 17 | Lame T-Shirt | 15 |
+------------+--------------------+-------+
Then you have some fancy-schmancy ajax that lists these puppies off as checkboxes.
Your hungry-hippo user selects 13, 15, 16
. No dessert for her today...
A way to summarize your user's order in one line, with pure mysql.
Use GROUP_CONCAT
with the the IN
clause:
mysql> SELECT GROUP_CONCAT(name SEPARATOR ' + ') AS order_summary FROM product WHERE product_id IN (13, 15, 16);
Which outputs:
+------------------------------------------------+
| order_summary |
+------------------------------------------------+
| Double Double + Animal Style Fries + Root Beer |
+------------------------------------------------+
If you want the total price too, toss in SUM()
:
mysql> SELECT GROUP_CONCAT(name SEPARATOR ' + ') AS order_summary, SUM(price) AS total FROM product WHERE product_id IN (13, 15, 16);
+------------------------------------------------+-------+
| order_summary | total |
+------------------------------------------------+-------+
| Double Double + Animal Style Fries + Root Beer | 10 |
+------------------------------------------------+-------+