SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd7153c262263f408f949944a4144ddce6d8757d3710916bb1874c0469d5c16d' 
  AND token = 'zf6b5655OcmfxjSGcenrzYqtAOlGtvdk8RRivaKHCAA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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