SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1068cb5e3498b19bc5cc564e143697c66b076eee22abf8c1c6977311b0015cd1' 
  AND token = '9hgWUCCiAttWuqJuLsbAHNhHDQM/rU4QYK25PVPk0Yg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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