SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd26ff4450e5f43bf68870813a5de9cbf71061798021d4f25139526d9c00100d5' 
  AND token = 'BKZP1ShMpcPdMFZb2Chh6DCrL/gOOw/gJiatEYhZ+Rw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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