Hi,
I'm using a database provider to access tables on my SQL server. The data are used in my strategy as signal line (via GetExternalSymbol).
My problem: when changing the data on the SQL and just looking on a chart of a symbol of these data as source everything is ok. But in my strategy the data will not be updated. I have to close the strategy and reopen it to get the updated data. I also tried to work with ClearExternalSymbols (it correctly tells that 1 symbol has been cleared) but there will always be shown the old (I think cached) data till I close and reopen the strategy.
I also tried to clear the cache for a specific symbol (e.g ClearExternalSymbols("MSFT")), but this seems to be an incorrect entry in the WealthScriptQuickRef (error message on compiling)
Greeting
Erich

Hi Erich,

Sounds like your code is improperly operating a class level variable or sort of that. To avoid guesswork please paste the skeleton code here for our review.

Hi Eugene,

CODE:
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Here's it, your improperly operated class variable that is not reset:

CODE:
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Move it inside the Execute() method body.

Hi Eugene,
it's working now - but from the view of programming not clear: Should not ClearExternalSymbols(); clear the cache?
In my oppinion if the cache would be cleared properly declaring the class variable inside the Execute() consumes extra memory (garbage collection in .net <4.0 is not the best...). This could be a problem when dealing with large count of symbols.

Greetings
Erich

Hi Erich,

The question has nothing to do with some "cache" or ClearExternalSymbols. From programming standpoint, your class level variable causes the behavior you described -- something reminding of this pattern which also uses a class level variable:

WealthScript Techniques | Don't execute Strategy on open

Re: memory usage, don't optimize before the code cries for optimization. It's safe to not be creative where it's not needed e.g. don't PrintDebug from constructor, don't create a class level variable where nobody else is doing it.