SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efb79d19bdd7e18f1d0d3cf073f896b9b65ade2b19d78b52bc58b12f620d721a' 
  AND token = 'M2jowUrOxbnBWPc7NhJshPrpn/xAg5/90qrYDZ7Js4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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