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You can do this with SQL Server Management Studio. → Right click the table design and go to Relationships and choose the foreign key on the left-side pane and in the right-side pane, expand the menu "INSERT and UPDATE specification" and select "Cascade" as Delete Rule. edited Nov 12, 2014 at 20:39. senshin.
20 cze 2013 · ON DELETE CASCADE: if a row of the referenced table is deleted, then all matching rows in the referencing table are deleted. ON DELETE SET NULL : if a row of the referenced table is deleted, then all referencing columns in all matching rows of the referencing table to be set to null.
25 wrz 2008 · The delete with the cascade option only applied to tables with foreign keys defined. If you do a delete, and it says you cannot because it would violate the foreign key constraint, the cascade will cause it to delete the offending rows. If you want to delete associated rows in this way, you will need to define the foreign keys first.
176. First drop your foreign key and try your above command, put add constraint instead of modify constraint. Now this is the command: ALTER TABLE child_table_name ADD CONSTRAINT fk_name FOREIGN KEY (child_column_name) REFERENCES parent_table_name (parent_column_name) ON DELETE CASCADE; edited Dec 25, 2016 at 15:02.
FOREIGN KEY (product_id) REFERENCES products (id) ON DELETE CASCADE. ON UPDATE CASCADE. )Engine=InnoDB; This way, you can delete a product OR a category, and only the associated records in categories_products will die alongside. The cascade won't travel farther up the tree and delete the parent product/category table.
18 sty 2020 · 183116. 1. You are correct to assume it is the database server and not Entity Framework Core that performs the cascade delete. So, no there is no way to let EF handle this. If the migration fails because the database server warns you about multiple cascade paths, it's because you haven't properly configured the fluent API.
Assume the author_id is set to on_delete=CASCADE. The DB will become active when an author is deleted. When an author is deleted, the Book table could reference an ID that does no longer exist. Meaning that a deletion of an Author might need a "cascading" deletion of a book.
20 gru 2011 · That is Oracle issuing a delete statement against CHILD for each record it's deleting in PARENT. A different question would be which of the two are more efficient: DELETE FROM CHILD WHERE PARENT_ID = 1; DELETE FROM PARENT WHERE PARENT_ID = 1; vs. DELETE FROM PARENT WHERE PARENT_ID = 1; both with on delete cascade enabled.
ElementCollection annotation does not have cascade attribute, because operations are always cascaded. When you remove your entity via EntityManager.remove(), operation is cascaded to the ElementCollection. You have to fetch all MonthlyReport entities you want to delete and call EntityManager.remove for each of them.
4 lut 2009 · KEY `type` (`typeId`) CONSTRAINT `myForeignKey` FOREIGN KEY (`typeId`) REFERENCES `types` (`id`) ON DELETE CASCADE ON UPDATE CASCADE. Just remember that you need to use the InnoDB storage engine: the default MyISAM storage engine doesn't support foreign keys. N.B., ON UPDATE CASCADE is probably a bad idea if you're using it to link a primary ...
