SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69ae7c09e52c3d1aa918bc4b4948e6e557595f6c61d07bd258173e3a442567fe' 
  AND token = '6VD/lUNJKpvLu03wmDL8eeAGRYhQWRTX/yRgrN6tKVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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