I had this following code in one of my finder statements:
:conditions => ["subscription_id IN (?)",subscription_ids.join(",")]
That was producing the SQL statement:
SELECT * FROM memberships WHERE (subscription_id IN ('640,610,641,639,642,620,645'))
But that statement didn't yield any result set.
Whereas the following code:
:conditions => "subscription_id IN (#{subscription_ids.join(',')})"
..produces the SQL statement:
SELECT * FROM memberships WHERE (subscription_id IN (640,610,641,639,642,620,645))
which gave me the correct result set.
The difference between the 2 SQL statements is the usage of single-quotes around the numbers.