Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2f37698937725d56dfc6fa9a5b6299ac76cb7f2354bddcaf4411829c5c565d80' 
  AND token = '71Mb+XdvvirNqZuMt6fPConaLfqFQRSIBmFpRabGgNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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