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Entity Framework and Default Values

In Entity Framework, Default value constraints functionality is not been achieved, I tried it myself and then read about it here. So, I want to know what is the best way to get this. Should I use a stored procedure or trigger something like that? And which will be better or something new has been added in Entity Framework as I don't want to handle it explicitly in code. It will be a great help.

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Wasim Bajwa Avatar asked Jan 16 '17 13:01

Wasim Bajwa


People also ask

How do I change the default value in Entity Framework?

You can set "StoredGeneratedProperty" attribute of table column in the EDMX file to Computed to enable default value insertion in entity framework.

How do you define a default value?

Default values, in the context of databases, are preset values defined for a column type. Default values are used when many records hold similar data.

How do you use default value?

Right-click the control that you want to change, and then click Properties or press F4. Click the All tab in the property sheet, locate the Default Value property, and then enter your default value. Press CTRL+S to save your changes.

What is a default value example?

A DEFAULT value clause in a data type specification explicitly indicates a default value for a column. Examples: CREATE TABLE t1 ( i INT DEFAULT -1, c VARCHAR(10) DEFAULT '', price DOUBLE(16,2) DEFAULT 0.00 ); SERIAL DEFAULT VALUE is a special case.


2 Answers

In Database First approach, the entity framework ignores the default value constraints. However the Entity Framework displays Default Value property for columns.In Model.edmx viewer select an entity -> go the column -> properties -> Default Value. Add the default value for the column in it and that's it.

In my case, i updated the Model.edmx file through code. The code gets the default constraints from Db and then updates the conceptual model in Model.edmx file as i have large number of default value columns.

Default value constraint issue persists in all the versions of Entity Framework till EF6 and seems to be resolved in Entity Framework 7

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Wasim Bajwa Avatar answered Oct 01 '22 05:10

Wasim Bajwa


The easiest way is to initialize your property from C# and thus ensure the default value.

For Database First, the designer ignores your SQL default and you have to tell it to treat your column as Computed: select your entity -> go the column -> properties -> set StoreGeneratedPattern to Computed (it defaults to None)

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Alexei - check Codidact Avatar answered Oct 01 '22 06:10

Alexei - check Codidact