SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6eca8bcae716a8b4e33be92ed4aa5abf3fa4525dcfb1fc318105bcf8f392c16b' 
  AND token = 'FTQ44hO34z0lBGsTnKhtR3+BTwDMEElyK/xDrZiccQc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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