SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92a83e3185168abe0d99d76e6f85702c75d6b625a232f7920ca53dd15bbc3d2f' 
  AND token = 'oBH6c6M3y/1bhsocRgL9vaiCCDFlSg7lo6J8UGwfTcg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}