Entity Framework 5 Best Practices for Record Updates

Update records in Entity Framework 5, developers often face the choice of multiple methods, each with its advantages and disadvantages. This article will explore three common methods and their limitations, and ultimately give the best solution.

Method 1: Load the original record and update the attributes one by one

This method requires loading the original record first and then manually updating each modified attribute. While this approach gives flexibility to specify the properties to be changed, it requires two database queries (one for loading and one for update).

Method 2: Load the original record and set the changed value

A more efficient way is to use CurrentValues.SetValues to update only the modified properties. However, this method requires that the view contains all record attributes, which can pose security risks to sensitive data.

Method 3: Attach the updated record and set the status to Modified

To minimize the number of database queries, you can attach updated records and set the status to Modified. While this method only requires a single query, it cannot specify the properties to be changed and also requires that the view contains all properties.

Best solution

In order to take into account the efficiency of attribute specification and minimize the efficiency of view and single database query, the following methods are recommended:

Code example:

db.Users.Attach(updatedUser);
var entry = db.Entry(updatedUser);
entry.Property(e => e.Email).IsModified = true;
// 其他需要修改的属性
db.SaveChanges();

This scheme first attaches an updated record, and then modifys the IsModified flag of a specific attribute. This ensures that only expected attributes are updated, and the efficiency of a single database query can be maintained.