oData 排序字段生成

跟踪SQL 发现生成的SQL中所有的字段都进行了排序，查看OData原代码，发现如果实体有Key，就按照Key asc 加上指定字段进行排序

属性 EnsureStableOrdering可以控制是否生成多个字段排序

Type: System.Boolean

A true value indicates the original query should be modified when necessary to guarantee a stable sort order. A false value indicates the sort order can be considered stable without modifying the query. Query providers that ensure a stable sort order should set this value to false. The default value is true.

            ODataQuerySettings settings = new ODataQuerySettings()
            {
                EnsureStableOrdering = false
            };

        // Returns a sorted list of all properties that may legally appear
        // in an OrderBy.  If the entity type has keys, all are returned.
        // Otherwise, when no keys are present, all primitive properties are returned.
        private static IEnumerable<IEdmStructuralProperty> GetAvailableOrderByProperties(ODataQueryContext context)
        {
            Contract.Assert(context != null);

            IEdmEntityType entityType = context.ElementType as IEdmEntityType;
            if (entityType != null)
            {
                IEnumerable<IEdmStructuralProperty> properties =
                    entityType.Key().Any()
                        ? entityType.Key()
                        : entityType
                            .StructuralProperties()
                            .Where(property => property.Type.IsPrimitive());

                // Sort properties alphabetically for stable sort
                return properties.OrderBy(property => property.Name);
            }
            else
            {
                return Enumerable.Empty<IEdmStructuralProperty>();
            }
        }