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Exchange of databases?

It seems that the goal of many ORM tools and user data access layers (DAO template, etc.) is to abstract the database to such an extent that you could change the entire database system with minimal work.

Following common DAL patterns is usually a good idea in the code, but it seems like there will never be minimal work to replace the database. (Cost, training, data migration, etc.)

Does anyone have experience replacing one database with another in a large system and solving code problems? Should you worry about abstracting the actual database from your code?

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Source: https://habr.com/ru/post/1703626/

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