public IEnumerable <KeyValuePair <byte[], byte[]> > Find(string indexName, byte[] lookupValue) // Find the specified indexName and lookupValue. { KeyValueStore indexStore = GetSecondaryIndex(indexName); foreach (var pair in indexStore.EnumerateFromKey(lookupValue)) // Loop over the values { var key = pair.Key; var value = pair.Value; // construct our index key pattern (lookupvalue | key), then lookup the value of the actual object using the key that was found; if the previous condition was not met, then we must have enumerated past the end of the indexed value if (ByteArray.CompareMemCmp(key, 0, lookupValue, 0, lookupValue.Length) == 0) { if (key.Length == (value.Length + lookupValue.Length) && ByteArray.CompareMemCmp(key, lookupValue.Length, value, 0, value.Length) == 0) { if (Get(value) != null) { yield return(new KeyValuePair <byte[], byte[]> (value, Get(value))); } else { yield break; } } } } }
public IEnumerable <KeyValuePair <byte[], byte[]> > FindStartsWith(string indexName, byte[] lookupValue) { KeyValueStore indexStore = GetSecondaryIndex(indexName); foreach (var pair in indexStore.EnumerateFromKey(lookupValue)) // Loops over the values. { var key = pair.Key; var value = pair.Value; // Constructs the index key pattern (lookupvalue | key), then looks up the value of the actual object using the discovered key: If the previous condition was not met, then we must have enumerated past the end of the indexed value. if (ByteArray.CompareMemCmp(key, 0, lookupValue, 0, lookupValue.Length) == 0) { if (key.Length >= (value.Length + lookupValue.Length)) { if (Get(value) != null) { yield return(new KeyValuePair <byte[], byte[]> (value, Get(value))); } else { yield break; } } } } }
public void RemoveIndexRangeForValue(string indexName, byte[] startAt, byte[] value) { KeyValueStore indexStore = GetSecondaryIndex(indexName); var pairs = indexStore.EnumerateFromKey(startAt); foreach (var pair in pairs) { if (ByteArray.CompareMemCmp(pair.Value, value) == 0) { indexStore.Delete(pair.Key); } if (ByteArray.CompareMemCmp(startAt, 0, pair.Key, 0, startAt.Length) == 0) { continue; // Exit index removal only when the projectID in the index key changes. } break; } }
public void RemoveUpdatedValuesFromIndex2() { string path = Path.GetFullPath ("TestData\\RemoveUpdatedValuesFromIndex2"); var timer = new Stopwatch (); using (var db = new KeyValueStore(path)) { db.Truncate (); int totalSize = 0; db.Manifest.Logger = msg => Console.WriteLine (msg); var indexed = new SortedDictionary<string, byte[]> (); int num_items = 1000; timer.Start (); for (int i = 0; i < num_items; i++) { indexed ["Mod"] = BitConverter.GetBytes (i % 100); db.Set (BitConverter.GetBytes (i), BitConverter.GetBytes (i), indexed); totalSize += 8 + 4; } timer.Stop (); Console.WriteLine ("Wrote data (with indexing) at a throughput of {0} MB/s", (double)totalSize / timer.Elapsed.TotalSeconds / (1024.0 * 1024.0)); timer.Reset (); timer.Start (); var ctModZeros = db.Find ("Mod", BitConverter.GetBytes ((int)0)).Count (); timer.Stop (); Assert.AreEqual (10, ctModZeros); Console.WriteLine ("Scanned index at a throughput of {0} items/s", (double)ctModZeros / timer.Elapsed.TotalSeconds); } // Open the index directly and see if the data is there using (var db = new KeyValueStore(Path.Combine(path, "Mod"))) { int num_vals = db.EnumerateFromKey (BitConverter.GetBytes ((int)0)).Count (pair => pair.Key.Take (4).All (b => b == 0)); Assert.AreEqual (10, num_vals); } // Re-open the main key-value store and update the value at 30 using (var db = new KeyValueStore(path)) { var indexed = new SortedDictionary<string, byte[]> (); indexed ["Mod"] = BitConverter.GetBytes (201 % 100); db.Set (BitConverter.GetBytes (200), BitConverter.GetBytes (200), indexed); // Clean the data from the index db.RemoveFromIndex (BitConverter.GetBytes (200), new Dictionary<string, byte[]> { { "Mod", BitConverter.GetBytes(200 % 100) } }); } // Open the index again directly and confirm that the lookup key is gone now as well using (var db = new KeyValueStore(Path.Combine(path, "Mod"))) { int num_vals = db.EnumerateFromKey (BitConverter.GetBytes ((int)0)).Count (pair => pair.Key.Take (4).All (b => b == 0)); Assert.AreEqual (9, num_vals); } }