Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '855dce72e072eb4a484f3c4c69a2576a03a51b4edd1c4352672c37fc3fb4e80f' 
  AND token = 'YXYa+uLSY964cgHgkdLh4ZnwHzi+US7BooyrlAxVR2E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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