Скачать или смотреть How to Update Records with ICollection in Entity Framework

Learn how to efficiently update records in Entity Framework along with ICollection, including how to handle insert and delete operations seamlessly.
---
This video is based on the question https://stackoverflow.com/q/77617477/ asked by the user 'Mohamed Asan Sali' ( https://stackoverflow.com/u/23024489/ ) and on the answer https://stackoverflow.com/a/77632650/ provided by the user 'Mohamed Asan Sali' ( https://stackoverflow.com/u/23024489/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions.

Visit these links for original content and any more details, such as alternate solutions, comments, revision history etc. For example, the original title of the Question was: How to update the records along with ICollection EF

Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l...
The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license.

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
How to Update Records with ICollection in Entity Framework

Updating records in a database using Entity Framework (EF) can be a straightforward task when dealing with simple entities. However, when you start incorporating collections like ICollection, things can get a bit tricky. Many developers face challenges and receive errors such as "one or more of the foreign-key properties is non-nullable" when attempting to update these collections. In this guide, we are going to discuss how to effectively update bank records and manage related collections using Entity Framework.

The Problem

You may find yourself in a situation where you want to update an entity that has associated child entities stored in collections. For example, when handling a FHASMstBank entity that has ICollection properties like FHASMstBankDomains and FHASMstBankProducts. If your updating strategy isn't correctly managing these collections, it may result in errors during the save operation. The common issues can arise from:

Attaching entities where foreign keys need to be handled carefully.

Maintaining referential integrity by ensuring that unmatched or stale records are removed or updated.

Inserting new child records when they do not already exist.

Solution Overview

To efficiently update your bank records while managing related collections, follow the structured approach outlined below. This strategy will ensure that:

You update existing records properly.

You insert new child records when necessary.

You remove old child records that are no longer relevant.

Step 1: Update the Parent Record

First, you should locate the parent entity (in this case, FHASMstBank) that you want to update. Then, update its properties accordingly.

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Handle Child Collections

Next, for each collection associated with the parent entity, you will need to perform three key operations: deleting, inserting, and updating the child entities.

A. Updating Geo Mappings

Remove old mappings that are not present in the new data:

[[See Video to Reveal this Text or Code Snippet]]

Add new mappings from the updated data:

[[See Video to Reveal this Text or Code Snippet]]

B. Updating Domains

Repeat the above steps for your domain entities:

Remove outdated domains:

[[See Video to Reveal this Text or Code Snippet]]

Insert new domains:

[[See Video to Reveal this Text or Code Snippet]]

C. Repeat for Other Collections

Repeat the same process for any other collections—like products and components—by following the pattern of removing outdated records and adding new ones.

Final Step: Save Changes

After managing all the child collections and updating the parent, you can call the SaveChanges() method to commit all the changes to the database.

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

Updating records with ICollection in Entity Framework doesn’t have to be a daunting task. By adopting a clear structure that involves updating the parent, followed by carefully managing the child collections through delete and insert operations, you can effectively avoid common pitfalls. This approach ensures that your database stays consistent and the integrity of relationships is maintained.

By following this guide, you'll be well on your way to updating your bank records with ease. If you encounter more specific issues or need to handle different types of relationships, consider adjusting the method based on the nuances of your data model.