SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd098c3384ded39a4a40819dfc2b27b6415e9ed26f53992463b8b86f634779f8' 
  AND token = 'WdA6RUe2rfMuPrh+Qt7PJdHdnVvSQPA+Wwqo4afTWqc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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