SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8001f0efc6788c4b3942addcaf560b7351527a7bf98974eaafeba62e3e3405c1' 
  AND token = 'LMoiwaif/AkTfsMzIJPVHAG0jmhFwyjB04T+N13ItqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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