/// <summary>Return the keys that are in the first range, but not in the others</summary>
/// <typeparam name="TKey">Type of the keys returned by the query</typeparam>
/// <param name="trans">Transaction used by the operation</param>
/// <param name="ranges">List of at least one key selector pairs</param>
/// <param name="keySelector">Lambda called to extract the keys from the ranges</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 <KeyValuePair <Slice, Slice> > Except <TKey>(this IFdbReadOnlyTransaction trans, IEnumerable <FdbKeySelectorPair> ranges, Func <KeyValuePair <Slice, Slice>, TKey> keySelector, IComparer <TKey> keyComparer = null)
{
//TODO: Range options ?
if (trans == null)
{
throw new ArgumentNullException("trans");
}
if (ranges == null)
{
throw new ArgumentNullException("ranges");
}
if (keySelector == null)
{
throw new ArgumentNullException("keySelector");
}
trans.EnsureCanRead();
return(new FdbExceptIterator <KeyValuePair <Slice, Slice>, TKey, KeyValuePair <Slice, Slice> >(
ranges.Select(range => trans.GetRange(range, new FdbRangeOptions {
Mode = FdbStreamingMode.Iterator
})),
default(int?),
keySelector,
TaskHelpers.Cache <KeyValuePair <Slice, Slice> > .Identity,
keyComparer
));
}
public static IAsyncEnumerable <KeyValuePair <Slice, Slice> > MergeSort <TKey>([NotNull] this IFdbReadOnlyTransaction trans, [NotNull] IEnumerable <KeySelectorPair> ranges, [NotNull] Func <KeyValuePair <Slice, Slice>, TKey> keySelector, IComparer <TKey> keyComparer = null)
{
//TODO: Range options ?
Contract.NotNull(trans, nameof(trans));
Contract.NotNull(ranges, nameof(ranges));
Contract.NotNull(keySelector, nameof(keySelector));
trans.EnsureCanRead();
return(new MergeSortAsyncIterator <KeyValuePair <Slice, Slice>, TKey, KeyValuePair <Slice, Slice> >(
ranges.Select(range => trans.GetRange(range, new FdbRangeOptions {
Mode = FdbStreamingMode.Iterator
})),
public static IFdbAsyncEnumerable <TResult> MergeSort <TKey, TResult>(this IFdbReadOnlyTransaction trans, IEnumerable <FdbKeySelectorPair> ranges, Func <KeyValuePair <Slice, Slice>, TKey> keySelector, Func <KeyValuePair <Slice, Slice>, TResult> resultSelector, IComparer <TKey> keyComparer = null)
{
//TODO: Range options ?
trans.EnsureCanRead();
return(new FdbMergeSortIterator <KeyValuePair <Slice, Slice>, TKey, TResult>(
ranges.Select(range => trans.GetRange(range, new FdbRangeOptions {
Mode = FdbStreamingMode.Iterator
})),
default(int?),
keySelector,
resultSelector,
keyComparer
));
}
public static IFdbAsyncEnumerable <KeyValuePair <Slice, Slice> > Except <TKey>([NotNull] this IFdbReadOnlyTransaction trans, IEnumerable <KeySelectorPair> ranges, Func <KeyValuePair <Slice, Slice>, TKey> keySelector, IComparer <TKey> keyComparer = null)
{
//TODO: Range options ?
Contract.NotNull(trans, nameof(trans));
Contract.NotNull(ranges, nameof(ranges));
Contract.NotNull(keySelector, nameof(keySelector));
trans.EnsureCanRead();
return(new FdbExceptIterator <KeyValuePair <Slice, Slice>, TKey, KeyValuePair <Slice, Slice> >(
ranges.Select(range => trans.GetRange(range, new FdbRangeOptions {
Mode = FdbStreamingMode.Iterator
})),
default(int?),
keySelector,
(kv) => kv,
keyComparer
));
}
public void EnsureCanRead()
{
m_transaction.EnsureCanRead();
}
