SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '066cc3e5321735ebccad7ef4b2a7b5531a58d15b937f3decb15a75f4e0862eec' 
  AND token = 'Tsg6uBLUVq5pYETkUEGvOexhmNvt0OuKoFHXIywOSNA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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