/// <summary>Return the keys that are in the first range, but not in the others</summary>
/// <typeparam name="TKey">Type of the keys used for the comparison</typeparam>
/// <typeparam name="TResult">Type of the results returned by the query</typeparam>
/// <param name="trans">Transaction used by the operation</param>
/// <param name="ranges">List of at least one key ranges</param>
/// <param name="keySelector">Lambda called to extract the keys used by the sort</param>
/// <param name="resultSelector">Lambda called to extract the values returned by the query</param>
/// <param name="keyComparer">Instance used to compare the keys returned by <paramref name="keySelector"/></param>
/// <returns>Async query that returns only the results that are in the first range, and not in any other range.</returns>
public static IFdbAsyncEnumerable <TResult> Except <TKey, TResult>(this IFdbReadOnlyTransaction trans, IEnumerable <FdbKeyRange> ranges, Func <KeyValuePair <Slice, Slice>, TKey> keySelector, Func <KeyValuePair <Slice, Slice>, TResult> resultSelector, IComparer <TKey> keyComparer = null)
{
if (ranges == null)
{
throw new ArgumentNullException("ranges");
}
return(Except <TKey, TResult>(trans, ranges.Select(r => FdbKeySelectorPair.Create(r)), keySelector, resultSelector, keyComparer));
}
/// <summary>Construct a query with a set of initial settings</summary>
internal FdbRangeQuery([NotNull] IFdbReadOnlyTransaction transaction, FdbKeySelector begin, FdbKeySelector end, [NotNull] Func <KeyValuePair <Slice, Slice>, T> transform, bool snapshot, FdbRangeOptions options)
{
Contract.Requires(transaction != null && transform != null);
this.Transaction = transaction;
this.Begin = begin;
this.End = end;
this.Transform = transform;
this.Snapshot = snapshot;
this.Options = options ?? new FdbRangeOptions();
this.OriginalRange = FdbKeySelectorPair.Create(begin, end);
}
public static FdbKeySelectorPair ToSelectorPair(this FdbSubspace subspace)
{
return(FdbKeySelectorPair.Create(subspace.ToRange()));
}