SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '203224739f9869d5eca8d27e4f03413b93441dbe21a0b688b75f176a1cb76a45' 
  AND token = 'l81OaAj5YwpyqmjNIgAxP+Bw9FMostPzDLiVybwax3g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}