Re-write cascade delete documentation #2996
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ajcvickers
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| uid: core/saving/cascade-delete | ||
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| # Cascade Delete | ||
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| Cascade delete is commonly used in database terminology to describe a characteristic that allows the deletion of a row to automatically trigger the deletion of related rows. A closely related concept also covered by EF Core delete behaviors is the automatic deletion of a child entity when it's relationship to a parent has been severed--this is commonly known as "deleting orphans". | ||
| Entity Framework Core (EF Core) represents relationships using foreign keys. An entity with a foreign key is the child or dependent entity in the relationship. This entity's foreign key value must match the primary key value (or an alternate key value) of the related principal/parent entity. |
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| Entity Framework Core (EF Core) represents relationships using foreign keys. An entity with a foreign key is the child or dependent entity in the relationship. This entity's foreign key value must match the primary key value (or an alternate key value) of the related principal/parent entity. | |
| When using a relational database, Entity Framework Core (EF Core) represents relationships using foreign keys. An entity with a foreign key is the child or dependent entity in the relationship. This entity's foreign key value must match the primary key value (or an alternate key value) of the related principal/parent entity. |
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This is also true for non-relational databases.
| > [!NOTE] | ||
| > This table is confusing and we plan to revisit this in a future release. See [GitHub Issue #21252](https://github.com/dotnet/efcore/issues/21252). | ||
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| The behaviors of `ON DELETE NO ACTION` and `ON DELETE RESTRICT` in relational databases are typically either identical or very similar. Despite what `NO ACTION` may imply, both of these options cause referential constraints to be enforced. The difference, when there is one, is _when_ the database checks the constraints. This is of academic interest only for most applications since it rarely effects behavior. Check your database documentation for the specific differences between `ON DELETE NO ACTION` and `ON DELETE RESTRICT` on your database system. |
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This is of academic interest only for most applications since it rarely effects behavior.
That may be a bit extreme - NO ACTION can be quite useful to temporary violate a deferred constraint within a transaction, in order to set the missing principal later in the same transaction (in PG and Sqlite).
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How about I remove "This is of academic interest only for most applications since it rarely effects behavior."?
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