Sort by order of values in a select statement “in” clause in mysql

Question

I\'m selecting a set of account records from a large table (millions of rows) with integer id values. As basic of a query as one gets, in a sense. What I\'m doing us build

Answer 1

Actually, this is better:

SELECT * FROM your_table
WHERE id IN (5,2,6,8,12,1)
ORDER BY FIELD(id,5,2,6,8,12,1);

heres the FIELD documentation:

http://dev.mysql.com/doc/refman/5.0/en/string-functions.html#function_field

Answer 2

If your query is 60K, that's a sign that you're doing it the wrong way.

There is no other way to order the result set than by using an ORDER BY clause. You could have a complicated CASE clause in your order by listing all the elements in your IN clause again, but then your query would probably be 120K.

I know you don't want to, but you should put the values in the IN clause in a table or a temporary table and join with it. You can also include a SortOrder column in the temporary table, and order by that. Databases like joins. Doing it this way will help your query to perform well.

Answer 3

A bit of a trick....

SELECT * FROM your_table
WHERE id IN (5,2,6,8,12,1)
ORDER BY FIND_IN_SET(id,'5,2,6,8,12,1') DESC;

note that the list of ID's in the find_in_set is a string, so its quoted. Also note that without DESC, they results are returned in REVERSE order to what the list specified.

Answer 4

You're first query surely uses an order by clause. So, you could just do a join, and use the same order by clause.

For example, if this was your first query

SELECT customer_id
  FROM customer  
 WHERE customer_id BETWEEN 1 AND 100 
ORDER
    BY last_name

And this was your second query

SELECT inventory_id
  FROM rental
 WHERE customer_id in (...the ordered list...)

Combined would be

SELECT r.inventory_id
  FROM rental r
INNER
  JOIN customer c
    ON r.customer_id = c.customer_id    
 WHERE c.customer_id BETWEEN 1 AND 100 
ORDER
    BY c.last_name