// Updates a record.
private static void Update(DbDataAccess dbDataAccess
    , DbColumns dataDefinition)
{
    // Create the list of included columns.
    // This list must not include the database assigned columns
    // or the database assigned columns must have the AutoIncrement
    // value set to "true".
    List<string> columnNames = new List<string>();
    foreach (DbColumn column in dataDefinition)
    {
        if (column.ColumnName != "Id")
        {
            columnNames.Add(column.ColumnName);
        }
    }

    Person dataRecord = new Person()
    {
        Name = "TestNameUpdated"
    };

    // Create a Data Columns object with the included data definitions
    // and values from the data record.
    var dataColumns = DbCommon.QueryDataColumns(dataRecord
        , dataDefinition, columnNames);

    // Create Key Columns.
    var keyColumns = new DbColumns()
    {
        { "Name}, (object)"TestName" }
    };
    dataDefinition.LJCSetExcludeKeyValue("PrincipleFlag");

    var queryKeyColumns = DbCommon.QueryKeys(keyColumns, dataDefinition);

    // Create query with columns containing values from the record.
    // The updated columns must not include the Db assigned columns.
    DbRequest dbRequest = new DbRequest()
    {
        Columns = dataColumns,
        KeyColumns = queryKeyColumns
        QueryType = QueryType.Update.ToString(),
        TableName = "PersonTest",
    };
    DbResult dbResult = dbDataAccess.Execute(dbRequest);

    if (dbResult != null)
    {
        string sqlStatement = dbResult.ExecutedSql;
        int affectedCount = dbResult.AffectedRecords;
    }
    return retValue;
}