MySql conditional order by
I have this table (simplified):
CREATE TABLE `my_table` (
`id` INT NOT NULL AUTO_INCREMENT ,
`item_name` VARCHAR(45) NULL ,
`price` DECIMAL(10,0) NULL ,
PRIMARY KEY (`id`)
)
I need to select all items from the table, ordered this way:
- items with
price > 0.00
first, ordered byprice ASC
- items with
price = 0.00
last, ordered byid
I tried this:
SELECT *
FROM my_table
WHERE 1
ORDER BY
CASE price WHEN !0.00 THEN price
ELSE id
END
ASC
And I get results like
item_name | price |
---|---|
foo | 150,00 |
bar | 0,00 |
baz | 500,00 |
hum | 0,00 |
How do I build the query to have
item_name | price |
---|---|
foo | 150,00 |
ba开发者_如何学JAVAz | 500,00 |
bar | 0,00 |
hum | 0,00 |
Thank you for your time
This will do the trick..
SELECT *
FROM my_table
WHERE 1
ORDER BY
CASE price WHEN 0 THEN 1
ELSE -1
END ASC, price asc, id asc
You can also use the following:
SELECT *
FROM my_table
WHERE 1
ORDER BY price=0, price, id;
The part 'price=0' will be 1 for items with zero price, 0 for items with non-zero price. As the default sort order is ASC, non-zero items are now placed first.
The next bit of the order-by clause means that non-zero items are then sorted by price (again ascending). If any items with non-zero price have the same price, they will be further sorted by id, but we don't care about that.
The last part is only there for items where price=0. As all these items do have the same price, the effect is to sort all the zero-priced items by id.
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