Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4888db190cbbe0df4eeeb063d1c6535f5082adbf2d3f860472cadef27748d67' 
  AND token = 'lf6XJ3JKS7/SNGu4XOQtmhi951nx11Sfr2d6n7r7IGA=' 
  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"
    }
  }
}