Optimistic Offline Lock

Many databases (including PostgreSQL and SQLite) don’t have an equivalent to SQL Server’s rowversion type. We could improve our support for optimistic concurrency on those stores by implementing the Optimistic Offline Lock pattern in the framework.

This would be similar to having a rowversion property in the entity except that EF would manage the value. When the entity is saved, somewhere in the update pipeline, we would automatically increment the property’s value. The DML would look something like this:

UPDATE Person
SET Name = "Brice", RowVersion = 24
WHERE RowVersion = 23;

[ajcvickers]

@m4rs2k Yes, 👍 this issue.

[roji]

FYI I found out PostgreSQL does have an automatically-updated xmin column which could be used as a concurrency token, much like SqlServer’s rowversion, so this may be less important for PostgreSQL. See https://github.com/npgsql/Npgsql.EntityFrameworkCore.PostgreSQL/issues/19.