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The inability to update a primary key has just pushed my entity framework project into the dumpster :*-(i can do this in sql, so why can't i do it using the entity framework? update mytable set myprimarykey = "yes my primary key has changed." as a work around i could add an identity field to every table and use it, but that would make my. Entity framework core supports composite keys - primary key values generated from two or more fields in the database. composite keys are not covered by conventions or data annotation attributes. the only way to configure composite keys is to use the haskey method.. One integer column which is the primary key called "id" and the other column a varchar(50) named "description". you can make the id column an auto-incremental field to reduce the hassle and make the "description" column a unique index. update the other tables to refer to the "id" column as a foreign key..

How to import composite entity through data import /export

Changes to key properties can only be made when the object is not being tracked or is in the added state. i tried to set the change tracker = false but the row status will remain unchanged even i successfully made the change to id2 field, therefore ef4 cannot detect changes and no update is trigger.. This is interesting to note; the setvalues method takes in a generic object and will update all the properties that match on both the entity and the object you pass into the setvalues method. you can also use dictionaries with property keys as the tuple key.. The following image shows a conceptual model that was created with the entity framework designer. the model contains two entities that participate in one-to-many relationship. both entities have navigation properties. course is the depend entity and has the departmentid foreign key property defined..

entity framework update key field

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