SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09dee593ca6de13911798682a8b981d335ceaad30c4ca044eca9edf9559603cf' 
  AND token = 'nlNMimZrgTUaiAzmQ8APR8hynQ9E7lHfsSxpc4BS55E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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