Load API SQL does not work with MariaDB

[bobvawter]

Follow-up to PR #937

The SQL based on a CTE doesn't work with MariaDB. There appears to be some kind of type coercion or parameter-encoding issue where the JOIN between the key CTE data and the base table results in no rows being matched. If this use-case must be supported, we could look at using a much simpler select statement that only matches a single row by PK.