SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92519ccc3674488a9baf27bf61c888bb9b4b6e519571af8cf2281162971467bc' 
  AND token = '2aNvZkzt61mgFtmQJTVE2QflDJ1KNyti55gVa+U7uMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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