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NHibernate & LINQ: Using the Fetch () Method with the Custom ToPagedList Method

I have a problem using the nHibernate Fetch () (or FetchMany ()) method with my swap method, which uses Futures to get the information they need. And I'm not sure how to fix it, but I know exactly what he is doing. Let me explain what I have so far.

I use the extension method found here so that I can count the number of rows as a value in the future. it looks like this.

public static IFutureValue<TResult> ToFutureValue<TSource, TResult>(this IQueryable<TSource> source, Expression<Func<IQueryable<TSource>, TResult>> selector) where TResult : struct
        {
            var provider = (NhQueryProvider)source.Provider;
            var method = ((MethodCallExpression)selector.Body).Method;
            var expression = Expression.Call(null, method, source.Expression);
            return (IFutureValue<TResult>)provider.ExecuteFuture(expression);
        }

It works fine using this, I can then combine getting the row count and getting my result set in a signature swap method that only generates one database access. My paging method looks like this.

public static IList<T> ToPagedList<T>(this IQueryable<T> query, int pageIndex, int pageSize, out int count)
        {
            var futureCount = query.ToFutureValue(x => x.Count());
            var futureResults = pageIndex == 0 && pageSize == 0 ? query.ToFuture() : query.Skip((pageIndex - 1) * pageSize).Take(pageSize).ToFuture();
            count = futureCount.Value;
            return futureResults.ToList();
        }

, .

repositoryInstance.Query().Where(x=>x.SomeTextField.Contains("lake")).ToPagedList(pageIndex, pageSize, out count);

. , .

repositoryInstance.Query().Where(x=>x.SomeTextField.Contains("lake")).FetchMany(x=>x.Details).ToPagedList(pageIndex, pageSize, out count);

QueryException " , ". - - , , Fetch(), , . ( , ), - . , , , Expression ToPagedList, , , . , , , , Fetch. ?

+3
1

ToPagedList :

public static IList<T> ToPagedList<T>(this IQueryable<T> query, int pageIndex,
                       int pageSize, out int count,
                       Func<IQueryable<T>, IQueryable<T>> filterResult)
{
    var futureCount = query.ToFutureValue(x => x.Count());
    //change only the results query, not the count one
    if (customAction != null)
        query = filterResult(query);
    var futureResults = pageIndex == 0 && pageSize == 0
                            ? query.ToFuture()
                            : query.Skip((pageIndex - 1) * pageSize)
                                   .Take(pageSize).ToFuture();
    count = futureCount.Value;
    return futureResults.ToList();
}

:

repositoryInstance.Query().Where(x => x.SomeTextField.Contains("lake"))
                  .ToPagedList(pageIndex, pageSize, out count,
                               q => q.FetchMany(x => x.Details));

, , , , .

+1

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