SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c87319455a4abebe24aa4fd5a734a8648c781548abd9ec7b5604e86da917004c' 
  AND token = 'LXLk2iqVTNWwF/CBP2ao3GNEFwAux65ZC5kAxBecl0k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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