SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cae6e6fb79859049eb426097ca4f39a80b6b1187a39973087676f7919ed93bf3' 
  AND token = 'yRVITHVKFcu5Dr40HGSirrgbfpKjUvJHX1c30ctwW58=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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