Document configuration of triggers for SaveChanges

[ehsan12021]

Hi,
I installed EF core version Preview 7 when I insert new record to a table that has a trigger I,ve got below error:

EF core preview 7 - latest preview release.

Error message:

Could not save changes because the target table has database triggers. Please configure your entity type accordingly, see https://aka.ms/efcore-docs-sqlserver-save-changes-and-triggers for more information.

thank you.

[ajcvickers]

@ehsan12021 This is expected behavior. Do you have some specific question about it?

[ehsan12021]

Thank you for your response.
How can I prevent an error ??
Temporarily I had to go back to stable version.6.0.5

[ajcvickers]

@roji Is this documented yet?

[roji]

@ajcvickers no, I'll definitely prioritize this given that people are starting to run into it.

[roji]

In the meantime, to resolve this, inform EF Core that the table in question has a trigger by calling HasTrigger():

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder.Entity<Blog>()
        .ToTable(tb => tb.HasTrigger("TriggerName"));
}

(the actual name doesn't matter at this point, since EF doesn't actually try to create the trigger - but that may change in the future)

[ehsan12021]

Thank you.
Mr @roji
and
Mr @ajcvickers .

[roji]

Reopening to also add documentation for the custom convention which adds a blank trigger everywhere, dotnet/efcore#28749.

[AndriySvyryd]

        protected override void ConfigureConventions(ModelConfigurationBuilder configurationBuilder)
        {
            configurationBuilder.Conventions.Add(_ => new BlankTriggerAddingConvention());
        }

public class BlankTriggerAddingConvention : IModelFinalizingConvention
{
    public virtual void ProcessModelFinalizing(
        IConventionModelBuilder modelBuilder,
        IConventionContext<IConventionModelBuilder> context)
    {
        foreach (var entityType in modelBuilder.Metadata.GetEntityTypes())
        {
            var table = StoreObjectIdentifier.Create(entityType, StoreObjectType.Table);
            if (table != null
                && entityType.GetDeclaredTriggers().All(t => t.GetDatabaseName(table.Value) == null))
            {
                entityType.Builder.HasTrigger(table.Value.Name + "_Trigger");
            }

            foreach (var fragment in entityType.GetMappingFragments(StoreObjectType.Table))
            {
                if (entityType.GetDeclaredTriggers().All(t => t.GetDatabaseName(fragment.StoreObject) == null))
                {
                    entityType.Builder.HasTrigger(fragment.StoreObject.Name + "_Trigger");
                }
            }
        }
    }
}

[robcyrier11]

/// <summary>
///     Called when a model is being finalized.
/// </summary>
/// <param name="modelBuilder">The builder for the model.</param>
/// <param name="context">Additional information associated with convention execution.</param>
public virtual void ProcessModelFinalizing(IConventionModelBuilder modelBuilder, IConventionContext<IConventionModelBuilder> context)
{
    foreach (var entityType in modelBuilder.Metadata.GetEntityTypes())
    {
        var table = StoreObjectIdentifier.Create(entityType, StoreObjectType.Table);
        if (table != null
            && entityType.GetDeclaredTriggers().All(t => t.GetName(table.Value) == null))
        {
            entityType.Builder.HasTrigger(table.Value.Name + "_Trigger");
        }

        foreach (var fragment in entityType.GetMappingFragments(StoreObjectType.Table))
        {
            if (entityType.GetDeclaredTriggers().All(t => t.GetName(fragment.StoreObject) == null))
            {
                entityType.Builder.HasTrigger(fragment.StoreObject.Name + "_Trigger");
            }
        }
    }
}

}

Trying to implement this but seems things have changed - IConventionTrigger no longer implements GetName(StoreObjectIdentifier). @AndriySvyryd do you have an alternative? Thanks!

[roji]

@robcyrier11 GetName has been renamed to GetDatabaseName - here are the docs for that convention.