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epsilonlabs / emc-ptcim

EMC driver for the PTC Integrity Modeler
Eclipse Public License 1.0
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Transaction limits in number of "changes" #7

Open arcanefoam opened 8 years ago

arcanefoam commented 8 years ago

Apparently there is a limit to the number of new elements that can be created within a transaction. Probably what we are experiencing is a limit on the number of changes that can be done inside a transaction. Wild guess is that the changes are stored in a table and thus limited by the maximum number of rows in the table (65k?).

In general this should not be an issue. The issue arises when generating models as for a big model it is easy to reach the limit (new elements + attribute settings). For the emg case we could have an additional flag to disable the transaction support. The other option is to disable it altogether.

kolovos commented 8 years ago

Almost all database-backed systems have a similar limitation. The problem is usually the memory they need to keep track of the uncommitted changes. The exact breaking point depends on how much memory is allocated to the database, what kind of changes are being made etc. so I don't think we can do much about this other than to propagate the exception to the user.