SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe069115895bb562755cbfc447376ffc649df342d30d6d0706cc76fb7d1cfe9b' 
  AND token = '4KBkn2SXok4Js4OgaHjWfg1nNhFqLR9Yixp8xCDVVFU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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