Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c08cbccf38f30f58730a709c57eaf5d8931be80e499cdfa7fb38d142b1dd8ca' 
  AND token = 'CnjxMxH3+GF+L1w4cKhf72nT3IRTgSNBS0V+KZs0Rk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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