SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2d736f4a7e603ec37bb3b323295ab4a157248e77b2ee9b240f0d7a87305ed5c' 
  AND token = 'wEWIWxFhmszMdubWFIPaasA041EDMjFLxaZm4oMoRQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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