Chagning Bars

[DangerBoy]

Hi Guys

A quick question to help with my understanding of how the chart data is being loaded, I am currently on the Gain Demo Feed, i have an issue where my charts are connected and loading bars for the day, a certain candle forms and my auto strat doesn't take the signal, I want to debug against this candle but the minute i disconnect and reconnect to my Gain feed the candles change. Now my understandnig is that this is because I have the use Ninja historical servers checked but my question is why is my chart reloading my local database with bars from Ninja Historical Database when this data has already been loaded. I was of the impression that when i'm on the live feed my bars are being stored locally and the only time they will change is if I clear my local and do a request for the data again. If i do a request for the data again without first clearing the database the request will just fill in the blank areas.

Is my understanding incorrect. I must be missing something as it doesn't explain why my candles change on disconnect and reconnect. I don't see that my local DB should be getting flushed and reloaded from NT historical servers.

Thanks
Ross

[NinjaTrader_Bertrand]

Ross, thanks for the post, it would reload data if your chosen range contains the current day, this link will help to clarify - http://www.ninjatrader-support.com/H...ricalData.html

[DangerBoy]

Thanks Bertrand, just what i was after.

So effectively if my local database contains the last 2 years of data and i make a request for the last 2 years and include the current day in my format data series, Ninja will clear out my entire 2 years local DB and reload the whole strip?

Just to futher clarify, when we say reload, are we talking the population of empty areas, or do we mean first an entire clear down of the data and then repopulate the lot?

Cheers
Ross

[NinjaTrader_Bertrand]

Hi Ross, no if you have 2 yrs of backdata and were connected earlier today and then take a break, come back on hour later and reconnect > NinjaTrader will reload the day then, not the entire history. In contrast if you select 'Reload historical data' by right clicking on the chart, it would attempt to reload the entire history then.

[DangerBoy]

Ok that makes far more sense, so what we are saying is that the current day on the chart is always reloaded regardless, I can't think of a scenario where this would not be the case, other than when it is already in the cache, however the historical will only be reloaded in the scenario where one specifically makes a format data series request and includes the current day or a period that is not contained in the local DB.?

Thanks
Ross

[NinjaTrader_Bertrand]

Yes, that's correct Ross.

[DangerBoy]

having thought through this a bit more it makes perfect sense that the active day needs reloading every time as it needs to load the most recent set of tick activity in synch with the previous daily activity before the disconnect.

Great, I'm more than happy with that then. Lastly sorry to pester you with all these questions. I just need help identifying at what points we have an explicit data fetch request being done.

1. If I open a brand new chart and specify 100days back in the format data series window, my thought is that this is not an explicit request. So i will get a current day refresh if not in cache and previous days loaded from local DB if data already exists with an explicit request done if not.

2. If I click on the reload data function from the menu and choose 100days back this is an explicit request and will cause a full clear and reload of the 100days.

3. Unsure about this one as I would think it should just be an extension of point 1. i.e change what my chart is looking at and refresh the current day, however i think it functions like point 2. , it's the step where If I already have a chart open and click on the Format Data Series option and change the settings from whatever the chart opened with, is it going to rerun an explicit request and clear the whole history if current day in series or will it just refresh current day and load history from local if it exists.

Cheers
Ross

[NinjaTrader_Bertrand]

Ross, you're welcome. It would use what is existing in the local database and cache, if the cache got cleared by .NET's garbage collection then it would incur a load from the provider if the current day is included in your request.