SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '006336470b9d2ac42545917170ff38a72dcdbdf53c1e0e8e49d534ccac1f5499' 
  AND token = '3wz1Ov75vQj6AsskvqU3eRqpZXE7x2qa8tcgqYJXkHs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}