Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd483f886078ff9fbbfbb6a6c1be5a463e8e4f2c79ac92ddd222f9c6cec7fea52' 
  AND token = 'NuBAGNriEMbtpCBc7llQXQXg1OAnhp3ER9fsrwQbifM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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