SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2659f54e19a17a53249c27e71f170a79962dc2d498537a495c0e81618fe5dfeb' 
  AND token = 'ySQF7GjCN7p6tmWA7ACLbh/zIXXe3PhvoqHvtPBqwgQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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