Double order in Mysql query

Question

I have some problems with Ordering in my SQL query.

I have 2 fields ('price' and 'in_stock')in table 'products'. What I want to do is to sort my query result by this 2 fields - by 'in_stock' and than by 'price'. BUT(!) one important thing is to order 'in_stock' as boolen. For example the table is:

Name       | Price | in_stock |
----------------------------------|
Product1   | 100   |    9     |
Product2   | 200   |    0     |
Product3   | 500   |    4     |
Product4   | 500   |    0     |
Product5   | 300   |    2     |

So right order result is:

Product1 - 100, 9
Product5 - 300, 2
Product3 - 500, 4
Product2 - 200, 0
Product4 - 500, 0 

First step - order products by stock - if product out of stock it must be at the end of list. After sort products by price - from lowest to highest.

Answer 1

您可以通过在ORDER子句中添加两列来按两列排序：

ORDER BY in_stock DESC, price ASC

Answer 2

You can use conditions in your order by clause:

select name, price, in_stock
from yourtable
order by in_stock = 0, price

This will order the products that have stock first (regardless of how many), then ordered by price.

---

Or you could use a case statement to order the results:

order by case when in_stock > 0 then 0 else 1 end, price

Answer 3

The ordering is not just adding 2 order clause, it needs additional case-when something as below to achieve the desired result set

select * from table_name 
order by case when in_stock = 0 then 1 else 0 end , price,in_stock desc ;