What is the best method with the generated code to do the following:

Say I have a table called ROLES

What I want to do is to do a quick check to see if a rolename = "Admin" exists in the table?

What I want is for it to just return true or false.

Thanks, Wade

create a filter and pull the object with that filter from the db. If the object could be loaded, it exists.

So is there an exception thrown if it does not exist? Or a boolean returned?

Also on the filter do I have to create a Index or Constraint on the Rolename column to do the ConstructFilter..... ?

Wade

Wade wrote:

So is there an exception thrown if it does not exist? Or a boolean returned?

Also on the filter do I have to create a Index or Constraint on the Rolename column to do the ConstructFilter..... ?

Wade

I would suggest taking a look at the documents. From the LLBLGenProRefrenceManual

DataAccessAdapterBase.FetchEntity Method Fetches an entity from the persistent storage into the passed in Entity2 object using a primary key filter. The primary key fields of the entity passed in have to have the primary key values. (Example: CustomerID has to have a value, when you want to fetch a CustomerEntity from the persistent storage into the passed in object)

[Visual Basic] Overridable Public Function FetchEntity( _ ByVal entityToFetch As IEntity2 _ ) As Boolean Implements _ IDataAccessAdapter.FetchEntity [C#] public virtual bool FetchEntity( IEntity2 entityToFetch ); Parameters entityToFetch The entity object in which the fetched entity data will be stored. The primary key fields have to have a value. Return Value true if the Fetch was succesful, false otherwise

Implements IDataAccessAdapter.FetchEntity

Remarks Will use a current transaction if a transaction is in progress, so MVCC or other concurrency scheme used by the database can be utilized

See Also DataAccessAdapterBase Class | SD.LLBLGen.Pro.ORMSupportClasses Namespace

Here is a copy of the code I am using to try to validate whether a role exists or not:

        private bool ValidWebRole( string role )
        {
            // Check for a zero value.
            if ( role.Length == 0 )
            {
                return false;
            }


            // Declare a DataAccessAdapter.
            DataAccessAdapter da = new DataAccessAdapter();

            RelationPredicateBucket filterBucket = new RelationPredicateBucket();
            IPredicate filterExpression = PredicateFactory.CompareValue( WebRoleFieldIndex.Role, ComparisonOperator.Equal, role );
            filterBucket.PredicateExpression.Add( filterExpression );
            WebRoleEntity webRoleEntity = new WebRoleEntity();


            // Check the database to see if the webRoleID is valid i.e. if it exists.
            if ( ! da.FetchEntity(webRoleEntity() ) ) 
            {
                return false;
            }
    
            da.CloseConnection();

            return true;
        }

How should this be done?

Thanks, Wade

Never Mind I figured it out.

Thanks, Wade