おそらくこれを試してください:
SET @rownum = 0;
SELECT id
FROM (SELECT *, @rownum:[email protected] + 1 AS id FROM dict ORDER BY words) d
WHERE d.words LIKE CONCAT('c','%')
単一のクエリとして、これを試してください:
SELECT id
FROM (SELECT *, @rownum:[email protected] + 1 AS id FROM dict, (SELECT @rownum:=0) r ORDER BY words) d
WHERE d.words LIKE CONCAT('c','%')