Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20147bcd6a409c2144e6dc568264733f83a9993f07e41003f7d2d9d5c790c7b3' 
  AND token = 'xQaTrhEP2MxNfIOumbYnMDbagA28tfyFExqg1iZ9gbE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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