Use of default symbol in MD entries

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Imported from previous forum

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The rule for specifying the symbol states that if the update action is New in an entry that is not the first and the reference entry ID is not specified and the symbol is not specified, then by default the symbol in the new entry is the same as the symbol in the previous entry.

My question is:
Does that include a previous entry whose action code is Delete?

[ I.e. does the symbol from a deleted entry also update the default Last Entry Symbol or not?]

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[ original email was from Ryan Pierce - rpierce@taltrade.com ]
> The rule for specifying the symbol states that if the update action is New in an entry that is not the first and the reference entry ID is not specified and the symbol is not specified, then by default the symbol in the new entry is the same as the symbol in the previous entry.
>
> My question is:
> Does that include a previous entry whose action code is Delete?
>
> [ I.e. does the symbol from a deleted entry also update the default Last Entry Symbol or not?]

Adding an MDEntry without specifying a symbol or an MDEntryRefID uses the same symbol as the previous MDEntry within the same FIX message. So if in one message, you have:

New MSFT
New (Symbol defaults to MSFT)
Change AAPL
New (Symbol defaults to AAPL)
Delete COMS
New (Symbol defaults to COMS)

Note that this default symbol can only happen within the same message. You cannot start a message with a New and no Symbol or MDEntryRefID. This is because while I consider it reasonable to keep track of the symbol of the last MDEntry you process within a FIX message, I don’t think it’s reasonable to keep such state across messages. Doing so is extremely error-prone.