Actually it's not possible to modify concurrently the project, this means two or more members can't modify the same project at the same moment. SqlDBM handle this as relational database does: a resource is locked by a transaction to prevent another transaction from accesing the same resource.
Let's suppose an user A decided to start working on the project, so the first thing that the user should do is lock the project. An user B wants to modify something, but once it enters to the project, a message will be displayed saying that the project is being edited by someone else (user A). Once user A finished the changes, then release the lock; thus user B can work at the project. Check below the workflow of how the lock - release works at SqlDBM.
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