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How to access entities that are not tracked?
The most common use of EntityEntry is to access the current EntityState of an entity. For example: The Entry method can also be used on entities that are not yet tracked. This does not start tracking the entity; the state of the entity is still Detatched.
Is the state of an entity tracked in EF6?
Unlike in EF6, setting the state of an individual entity will not cause all connected entities to be tracked. This makes setting the state this way a lower-level operation than calling Add, Attach, or Update, which operate on an entire graph of entities. The following table summarizes ways to use an EntityEntry to work with an entire entity:
Can a returned entityentry be used to track an entity?
This does not start tracking the entity; the state of the entity is still Detatched. However, the returned EntityEntry can then be used to change the entity state, at which point the entity will become tracked in the given state. For example, the following code will start tracking a Blog instance as Added:
What does local do for entityentry in EF Core?
DbSet .Local returns actual entities (not EntityEntry instances) for entities of the entity type represented by the DbSet. Each of these is described in more detail in the sections below.
How to update the current value of an entity?
The current or original values of an entity can be updated by copying values from another object. For example, consider a BlogDto data transfer object (DTO) with the same properties as the entity type: This can be used to set the current values of a tracked entity using PropertyValues.SetValues:
How to find an entity in a database?
DbContext.Find, DbContext.FindAsync, DbSet .Find, and DbSet .FindAsync are designed for efficient lookup of a single entity when its primary key is known. Find first checks if the entity is already tracked, and if so returns the entity immediately. A database query is only made if the entity is not tracked locally.