private IEnumerable <SubFingerprintData> ReadSubFingerprints(int[] hashes, int thresholdVotes,
IDictionary <string, string> yesMetaFieldsFilters,
IDictionary <string, string> noMetaFieldsFilters,
ReadOnlyTransaction tx)
{
var subFingeprintIds = GetSubFingerprintMatches(hashes, thresholdVotes, tx);
var subFingerprints = subFingeprintIds.Select(tx.GetSubFingerprint);
if (yesMetaFieldsFilters.Count > 0 || noMetaFieldsFilters.Count > 0)
{
return(subFingerprints
.GroupBy(subFingerprint => subFingerprint.TrackReference)
.Where(group =>
{
var trackData = tx.GetTrackByReference(group.Key);
var result = metaFieldsFilter.PassesFilters(trackData.MetaFields, yesMetaFieldsFilters, noMetaFieldsFilters);
return result;
})
.SelectMany(x => x.ToList())
.Select(e => e.ToSubFingerprintData()));
}
return(subFingerprints
.Select(e => e.ToSubFingerprintData()));
}
private IEnumerable <SubFingerprintData> ReadSubFingerprints(int[] hashes, int thresholdVotes,
IDictionary <string, string> metaFieldsFilter,
ReadOnlyTransaction tx)
{
var subFingeprintIds = GetSubFingerprintMatches(hashes, thresholdVotes, tx);
var subFingerprints = subFingeprintIds.Select(tx.GetSubFingerprint);
if (metaFieldsFilter.Count > 0)
{
return(subFingerprints
.GroupBy(subFingerprint => subFingerprint.TrackReference)
.Where(group =>
{
var trackData = tx.GetTrackByReference(group.Key);
return trackData.MetaFields
.Join(metaFieldsFilter, x => x.Key, x => x.Key, (a, b) => a.Value.Equals(b.Value))
.Any(x => x);
})
.SelectMany(x => x.ToList())
.Select(e => e.ToSubFingerprintData()));
}
return(subFingerprints
.Select(e => e.ToSubFingerprintData()));
}
void SearchDatabase()
{
ReadOnlyTransaction t = db.StartReadWriteTransaction();
// Find all patients with age > 50 which are diagnosed flu in last September
foreach (Item patient in t.Find(Predicate.Value("age") > 50
& Predicate.Value("diagnosis").In(Predicate.Value("date").Between("2010-09-01", "2010-09-30")
& Predicate.Value("disease").In(Predicate.Value("name") == "flu"))))
{
Console.WriteLine("Patient " + patient.GetString("name") + ", age " + patient.GetNumber("age"));
}
// Print list of diseases with high temperature symptom ordered by name
foreach (Item disease in t.Find(Predicate.Value("class") == "disease"
& Predicate.Value("symptoms") == "high temperature",
new OrderBy("name")))
{
Console.WriteLine("Diseas " + disease.GetString("name"));
Object symptoms = disease.GetAttribute("symptoms");
if (symptoms is String)
{
Console.WriteLine("Symptom: " + symptoms);
}
else if (symptoms is String[])
{
Console.WriteLine("Symptoms: ");
String[] ss = (String[])symptoms;
for (int i = 0; i < ss.Length; i++)
{
Console.WriteLine("{0}: {1}", i, ss[i]);
}
}
}
t.Commit();
}
private void LoadLastTermAndIndex(ReadOnlyTransaction tx)
{
using (var c = _logDb.OpenReadOnlyCursor(tx))
{
var k = LogKey;
StoredLogEntryHeader value = new StoredLogEntryHeader()
{
Index = long.MaxValue
};
if (c.TryFindDup(Lookup.LE, ref k, ref value))
{
this.LastIndex = value.Index;
this.LastEntryTerm = value.Term;
}
}
}
public static unsafe bool TryGet(this ReadOnlyTransaction tx, Database db, Bufferable key, out Bufferable value)
{
value = default;
fixed(byte *keyPtr = &key.Buffer[0])
{
var keydb = new DirectBuffer(key.Buffer.Length, keyPtr);
DirectBuffer valuedb = default;
var success = db.TryGet(tx, ref keydb, out valuedb);
if (success)
{
value = new Bufferable(valuedb.Span.ToArray());
}
return(success);
}
}
void SearchDatabase()
{
ReadOnlyTransaction t = db.StartReadWriteTransaction();
DateTime start = DateTime.Now;
int nBooks = nAuthors * nBooksPerAutor / nCoauthors;
for (int i = 0, j = 0; i < nBooks; i++)
{
// find authors of the book
Item[] authors = Enumerable.ToArray(t.Find(Predicate.Value("-author").In(Predicate.Value("title") == GenerateTitle(i))));
Debug.Assert(authors.Length == nCoauthors);
for (int k = 0; k < nCoauthors; k++)
{
Debug.Assert(authors[k].GetString("name") == GenerateName(j++ % nAuthors));
}
}
for (int i = 0; i < nAuthors; i++)
{
// find book written by this author
Item[] books = Enumerable.ToArray(t.Find(Predicate.Value("author").In(Predicate.Value("name") == GenerateName(i))));
Debug.Assert(books.Length == nBooksPerAutor);
}
Console.WriteLine("Elapsed time for searching database " + (DateTime.Now - start));
start = DateTime.Now;
for (int i = 0, mask = 0; i < nBooks; i++, mask = ~mask)
{
// find book using full text search part of book title and ISDN
FullTextSearchResult result = t.FullTextSearch(GenerateWord(i ^ mask) + " " + GenerateISBN(i), MAX_FULL_TEXT_SEARCH_RESULTS, MAX_FULL_TEXT_SEARCH_TIME);
Debug.Assert(result.Hits.Length == 1);
}
for (int i = 0, mask = 0; i < nAuthors; i++, mask = ~mask)
{
// find authors using full text search of author's name
FullTextSearchResult result = t.FullTextSearch(GenerateName(i ^ mask), MAX_FULL_TEXT_SEARCH_RESULTS, MAX_FULL_TEXT_SEARCH_TIME);
Debug.Assert(result.Hits.Length == 1);
}
Console.WriteLine("Elapsed time for full text search " + (DateTime.Now - start));
t.Commit();
}
public static unsafe bool TryGetDuplicate(this ReadOnlyTransaction tx, Database db, Bufferable key, ref Bufferable value)
{
using (var c = db.OpenReadOnlyCursor(tx))
{
fixed(byte *keyPtr = &key.Buffer[0], valPtr = &value.Buffer[0])
{
var keydb = new DirectBuffer(key.Buffer.Length, keyPtr);
var valuedb = new DirectBuffer(value.Buffer.Length, valPtr);
var success = c.TryFindDup(Lookup.EQ, ref keydb, ref valuedb);
if (success)
{
value = new Bufferable(valuedb.Span.ToArray());
}
return(success);
}
}
}
private static IEnumerable <ulong> GetSubFingerprintMatches(IReadOnlyList <int> hashes, int thresholdVotes, ReadOnlyTransaction tx)
{
var counter = new Dictionary <ulong, int>();
for (var table = 0; table < hashes.Count; ++table)
{
var hashBin = hashes[table];
var ids = tx.GetSubFingerprintsByHashTableAndHash(table, hashBin);
foreach (var id in ids)
{
counter.TryGetValue(id, out var count);
counter[id] = count + 1;
}
}
return(counter
.Where(pair => pair.Value >= thresholdVotes)
.Select(p => p.Key));
}
