SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7fcab2d23ba72f6502d21f92b2b20cbf04693b1ce7e225e9652912f0c70addc' 
  AND token = 'Tl8uJy/tsOZZuolhwY8CQz6kWBrleXBRA225D9EkdB0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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