-- add idea of a mix having mp3 as well as ogg

ALTER TABLE mixes RENAME COLUMN md5 TO ogg_md5;
ALTER TABLE mixes RENAME COLUMN length TO ogg_length;
ALTER TABLE mixes RENAME COLUMN url TO ogg_url;

ALTER TABLE mixes ADD COLUMN mp3_md5 VARCHAR(100);
ALTER TABLE mixes ADD COLUMN mp3_length INTEGER;
ALTER TABLE mixes ADD COLUMN mp3_url VARCHAR(1024);