SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f90d4f4e35432bbba6b46ad7e59b33bf54a862d0c0f0034ac760c4877cc926e7' 
  AND token = 'ogh9+G+8hPvTOlrefN/ZhgPXUNiIarFCIxZd64wmkC8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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