SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa38de494c92b5d915b242950e9f2898ddc37433f99daa93c4b70e664e7ec634' 
  AND token = 'q5vrNylkPhxkpI6A+OjwzZXtJlzF+oLdmvq9rgPMJZ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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