Additional Info About Order IDs
You receive Order IDs in the standard exchange's form with no additional remapping. Note that all exchanges have different rules about Order ID assignment:
Some exchanges have Order IDs that are unique globally across all securities. For example, Nasdaq TotalView exchange.
Some exchanges have Order IDs that are unique only per instrument. Two orders with the same Order IDs may exist for different instruments.
Some exchanges have Order IDs that are unique only per instrument per side. The same Order ID may exist on both (buy and sell) sides of the book for one instrument. For example, Borsa Istanbul exchange.
Most exchanges reuse Order IDs. The time period for reusing an Order ID may vary from one day to one week or more. Therefore, data can be valid only during some specific trade days.