DbExpressions.SqlQueryTranslator.VisitUpdateExpression C# (CSharp) Method

        protected override DbExpression VisitUpdateExpression(DbUpdateExpression updateExpression)
        {
            var sb = new StringBuilder();
            bool isAliased = false;
            if (updateExpression.Target.ExpressionType == DbExpressionType.Alias)
            {
                sb.AppendFormat("UPDATE {0} ", Visit(((DbAliasExpression) updateExpression.Target).Target));
                isAliased = true;
            }
            else
                sb.AppendFormat("UPDATE {0} ", Visit(updateExpression.Target));
            sb.AppendLine();
            if (!updateExpression.SetExpression.IsNull())
            {
                sb.AppendFormat("SET {0} ", Visit(updateExpression.SetExpression));
            }

            //If the target table is aliased, we asume that the same alias is used in the FROM clause
            if (!updateExpression.FromExpression.IsNull())
            {
                sb.AppendLine();
                sb.AppendLine("FROM ");
                sb.AppendFormat(1, "{0} ", Visit(updateExpression.FromExpression));
            }
            //If the target table is aliased we need to add a FROM clause
            else if (updateExpression.FromExpression.IsNull() && isAliased)
            {
                sb.AppendLine();
                sb.AppendLine("FROM ");
                sb.AppendFormat(1, "{0} ", Visit(updateExpression.Target));
            }

            if (!updateExpression.WhereExpression.IsNull())
            {
                sb.AppendLine();
                sb.AppendLine("WHERE ");
                sb.AppendFormat(1, "{0} ", Visit(updateExpression.WhereExpression));
            }

            return ExpressionFactory.Sql(sb.ToString().Trim());
        }