SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '197573e5045dfda2454eadec1e0222af4affeb1c5313dd6aaf58e6a3d903b364' 
  AND token = 'zXzqCkFTSAZfI5L7iURaG7u6WQk09EJ/aZxySeAJgDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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