[Beanis]

Postgres bulk update:

http://sqlfiddle.com/#!17/b3d19/1

You can do something similar in MySQL with temp tables.

Bulk update through upsert (slightly different than a bulk update, since it can create rows too)

MySQL: http://sqlfiddle.com/#!9/a6f050/1

Postgres: http://sqlfiddle.com/#!17/a8367/1

[imtringued]

And preferably you use the postgres specific "unnest(array1, array2, ...)" function which turns array parameters passed into the query into a temporary table that you can query.

    UPDATE example
    SET position = CAST(temp.position AS INTEGER)
    FROM unnest(:ids, :positions) AS temp (id, position)
    WHERE example.id = CAST(temp.id AS INTEGER);

[adrianmonk]

OK, so SQL extensions, so just the usual reasons to do bulk changes. I thought they might have mentioned it here because there was something unique to say about it in the context of this problem.