駅名候補、何も検証していないが
こんな感じか。
SELECT name
FROM eki
WHERE name LIKE '%:query%'
ORDER BY name
---
SELECT name
FROM (
SELECT name
, CASE WHEN name = ':query' THEN 2 WHEN name LIKE ':query%' THEN 1 ELSE 0 END AS priority
FROM eki
WHERE name LIKE '%:query%'
) e
ORDER BY priority DESC, name