Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3816d1fed61086f5d73c1f3c60a3f058917bf678bee599529e9ded3eefc8277' 
  AND token = 'PhNZAOyWfCoDgRqe3Cymk/uNCtAoYc7/kGQEr2/P3uo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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