public Store(string path)
{
var families = new ColumnFamilies();
db = RocksDb.OpenReadOnly(Options.Default, Path.GetFullPath(path), families, false);
defaultFamily = db.GetDefaultColumnFamily();
}
static void Main(string[] args)
{
string temp = Path.GetTempPath();
string path = Environment.ExpandEnvironmentVariables(Path.Combine(temp, "rocksdb_cf_example"));
var options = new DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true);
var columnFamilies = new ColumnFamilies
{
{ "reverse", new ColumnFamilyOptions() },
};
using (var db = RocksDb.Open(options, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
db.Put("one", "uno");
db.Put("two", "dos");
db.Put("three", "tres");
db.Put("uno", "one", cf: reverse);
db.Put("dos", "two", cf: reverse);
db.Put("tres", "three", cf: reverse);
}
using (var db = RocksDb.Open(options, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
string uno = db.Get("one");
string one = db.Get("uno", cf: reverse);
string nada;
nada = db.Get("uno");
nada = db.Get("one", cf: reverse);
}
using (var db = RocksDb.Open(options, path, columnFamilies))
{
db.DropColumnFamily("reverse");
var reverse = db.CreateColumnFamily(new ColumnFamilyOptions(), "reverse");
var nada = db.Get("uno", cf: reverse);
db.Put("red", "rouge", cf: reverse);
}
using (var db = RocksDb.Open(options, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
var nada = db.Get("uno", cf: reverse);
var rouge = db.Get("red", cf: reverse);
}
using (var db = RocksDb.OpenReadOnly(options, path, columnFamilies, false))
{
string uno = db.Get("one");
}
}
public CheckpointStore(string path)
{
db = RocksDb.OpenReadOnly(new DbOptions(), path, RocksDbStore.ColumnFamilies, false);
var metadataColumnHandle = db.GetColumnFamily(RocksDbStore.METADATA_FAMILY);
blocks = new DataTracker <UInt256, BlockState>(db, RocksDbStore.BLOCK_FAMILY);
transactions = new DataTracker <UInt256, TransactionState>(db, RocksDbStore.TX_FAMILY);
accounts = new DataTracker <UInt160, AccountState>(db, RocksDbStore.ACCOUNT_FAMILY);
_unspentCoins = new DataTracker <UInt256, UnspentCoinState>(db, RocksDbStore.UNSPENT_COIN_FAMILY);
spentCoins = new DataTracker <UInt256, SpentCoinState>(db, RocksDbStore.SPENT_COIN_FAMILY);
validators = new DataTracker <ECPoint, ValidatorState>(db, RocksDbStore.VALIDATOR_FAMILY);
assets = new DataTracker <UInt256, AssetState>(db, RocksDbStore.ASSET_FAMILY);
contracts = new DataTracker <UInt160, ContractState>(db, RocksDbStore.CONTRACT_FAMILY);
storages = new DataTracker <StorageKey, StorageItem>(db, RocksDbStore.STORAGE_FAMILY);
headerHashList = new DataTracker <UInt32Wrapper, HeaderHashList>(db, RocksDbStore.HEADER_HASH_LIST_FAMILY);
validatorsCount = new MetadataTracker <ValidatorsCountState>(db, RocksDbStore.VALIDATORS_COUNT_KEY, metadataColumnHandle);
blockHashIndex = new MetadataTracker <HashIndexState>(db, RocksDbStore.CURRENT_BLOCK_KEY, metadataColumnHandle);
headerHashIndex = new MetadataTracker <HashIndexState>(db, RocksDbStore.CURRENT_HEADER_KEY, metadataColumnHandle);
}
public override void Execute()
{
var popts = new PlaneDBOptions().DisableJournal();
if (!string.IsNullOrEmpty(Owner.Passphrase))
{
popts = popts.EnableEncryption(Owner.Passphrase);
}
else if (Owner.Compressed)
{
popts = popts.EnableCompression();
}
if (!string.IsNullOrEmpty(Owner.Tablespace))
{
popts = popts.UsingTableSpace(Owner.Tablespace);
}
if (From == null)
{
throw new GetOptException("No from");
}
if (To == null)
{
throw new GetOptException("No to");
}
using var rocks = RocksDb.OpenReadOnly(new DbOptions(), From.FullName, false);
using var plane = new PlaneDB(To, FileMode.OpenOrCreate, popts);
plane.OnFlushMemoryTable += (_, __) => Console.WriteLine("Flushed memory table");
plane.OnMergedTables += (_, __) => Console.WriteLine("Merged tables");
plane.Clear();
var iter = rocks.NewIterator();
plane.MassInsert(() => CopyFromRocks(plane, iter));
Console.WriteLine($"{copyCount:N0} entries copied in total");
}
public void FunctionalTest()
{
string temp = Path.GetTempPath();
var testdb = Path.Combine(temp, "functional_test");
string path = Environment.ExpandEnvironmentVariables(testdb);
if (Directory.Exists(testdb))
{
Directory.Delete(testdb, true);
}
var options = new DbOptions()
.SetCreateIfMissing(true)
.EnableStatistics();
// Using standard open
using (var db = RocksDb.Open(options, path))
{
// With strings
string value = db.Get("key");
db.Put("key", "value");
Assert.Equal("value", db.Get("key"));
Assert.Null(db.Get("non-existent-key"));
db.Remove("key");
Assert.Null(db.Get("value"));
// With bytes
db.Put(Encoding.UTF8.GetBytes("key"), Encoding.UTF8.GetBytes("value"));
Assert.True(BinaryComparer.Default.Equals(Encoding.UTF8.GetBytes("value"), db.Get(Encoding.UTF8.GetBytes("key"))));
// non-existent kiey
Assert.Null(db.Get(new byte[] { 0, 1, 2 }));
db.Remove(Encoding.UTF8.GetBytes("key"));
Assert.Null(db.Get(Encoding.UTF8.GetBytes("key")));
db.Put(Encoding.UTF8.GetBytes("key"), new byte[] { 0, 1, 2, 3, 4, 5, 6, 7 });
// With buffers
var buffer = new byte[100];
long length = db.Get(Encoding.UTF8.GetBytes("key"), buffer, 0, buffer.Length);
Assert.Equal(8, length);
Assert.Equal(new byte[] { 0, 1, 2, 3, 4, 5, 6, 7 }, buffer.Take((int)length).ToList());
// Write batches
// With strings
using (WriteBatch batch = new WriteBatch()
.Put("one", "uno")
.Put("two", "deuce")
.Put("two", "dos")
.Put("three", "tres"))
{
db.Write(batch);
}
Assert.Equal("uno", db.Get("one"));
// With save point
using (WriteBatch batch = new WriteBatch())
{
batch
.Put("hearts", "red")
.Put("diamonds", "red");
batch.SetSavePoint();
batch
.Put("clubs", "black");
batch.SetSavePoint();
batch
.Put("spades", "black");
batch.RollbackToSavePoint();
db.Write(batch);
}
Assert.Equal("red", db.Get("diamonds"));
Assert.Equal("black", db.Get("clubs"));
Assert.Null(db.Get("spades"));
// With bytes
var utf8 = Encoding.UTF8;
using (WriteBatch batch = new WriteBatch()
.Put(utf8.GetBytes("four"), new byte[] { 4, 4, 4 })
.Put(utf8.GetBytes("five"), new byte[] { 5, 5, 5 }))
{
db.Write(batch);
}
Assert.True(BinaryComparer.Default.Equals(new byte[] { 4, 4, 4 }, db.Get(utf8.GetBytes("four"))));
// Snapshots
using (var snapshot = db.CreateSnapshot())
{
var before = db.Get("one");
db.Put("one", "1");
var useSnapshot = new ReadOptions()
.SetSnapshot(snapshot);
// the database value was written
Assert.Equal("1", db.Get("one"));
// but the snapshot still sees the old version
var after = db.Get("one", readOptions: useSnapshot);
Assert.Equal(before, after);
}
var two = db.Get("two");
Assert.Equal("dos", two);
// Iterators
using (var iterator = db.NewIterator(
readOptions: new ReadOptions()
.SetIterateUpperBound("t")
))
{
iterator.Seek("k");
Assert.True(iterator.Valid());
Assert.Equal("key", iterator.StringKey());
iterator.Next();
Assert.True(iterator.Valid());
Assert.Equal("one", iterator.StringKey());
Assert.Equal("1", iterator.StringValue());
iterator.Next();
Assert.False(iterator.Valid());
}
// MultiGet
var multiGetResult = db.MultiGet(new[] { "two", "three", "nine" });
Assert.Equal(
expected: new[]
{
new KeyValuePair <string, string>("two", "dos"),
new KeyValuePair <string, string>("three", "tres"),
new KeyValuePair <string, string>("nine", null)
},
actual: multiGetResult
);
}
// Test with column families
var optionsCf = new DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true);
var columnFamilies = new ColumnFamilies
{
{ "reverse", new ColumnFamilyOptions() },
};
using (var db = RocksDb.Open(optionsCf, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
db.Put("one", "uno");
db.Put("two", "dos");
db.Put("three", "tres");
db.Put("uno", "one", cf: reverse);
db.Put("dos", "two", cf: reverse);
db.Put("tres", "three", cf: reverse);
}
// Test Cf Delete
using (var db = RocksDb.Open(optionsCf, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
db.Put("cuatro", "four", cf: reverse);
db.Put("cinco", "five", cf: reverse);
Assert.Equal("four", db.Get("cuatro", cf: reverse));
Assert.Equal("five", db.Get("cinco", cf: reverse));
byte[] keyBytes = Encoding.UTF8.GetBytes("cuatro");
db.Remove(keyBytes, reverse);
db.Remove("cinco", reverse);
Assert.Null(db.Get("cuatro", cf: reverse));
Assert.Null(db.Get("cinco", cf: reverse));
}
// Test list
{
var list = RocksDb.ListColumnFamilies(optionsCf, path);
Assert.Equal(new[] { "default", "reverse" }, list.ToArray());
}
// Test reopen with column families
using (var db = RocksDb.Open(optionsCf, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
Assert.Equal("uno", db.Get("one"));
Assert.Equal("one", db.Get("uno", cf: reverse));
Assert.Null(db.Get("uno"));
Assert.Null(db.Get("one", cf: reverse));
}
// Test dropping and creating column family
using (var db = RocksDb.Open(options, path, columnFamilies))
{
db.DropColumnFamily("reverse");
var reverse = db.CreateColumnFamily(new ColumnFamilyOptions(), "reverse");
Assert.Null(db.Get("uno", cf: reverse));
db.Put("red", "rouge", cf: reverse);
Assert.Equal("rouge", db.Get("red", cf: reverse));
}
// Test reopen after drop and create
using (var db = RocksDb.Open(options, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
Assert.Null(db.Get("uno", cf: reverse));
Assert.Equal("rouge", db.Get("red", cf: reverse));
}
// Test read only
using (var db = RocksDb.OpenReadOnly(options, path, columnFamilies, false))
{
Assert.Equal("uno", db.Get("one"));
}
// Test SstFileWriter
{
var envOpts = new EnvOptions();
var ioOpts = new ColumnFamilyOptions();
var sst = new SstFileWriter(envOpts, ioOpts);
var filename = Path.Combine(temp, "test.sst");
if (File.Exists(filename))
{
File.Delete(filename);
}
sst.Open(filename);
sst.Add("four", "quatro");
sst.Add("one", "uno");
sst.Add("two", "dos");
sst.Finish();
using (var db = RocksDb.Open(options, path, columnFamilies))
{
Assert.NotEqual("four", db.Get("four"));
var ingestOptions = new IngestExternalFileOptions()
.SetMoveFiles(true);
db.IngestExternalFiles(new string[] { filename }, ingestOptions);
Assert.Equal("quatro", db.Get("four"));
}
}
// test comparator
unsafe {
var comparator = new IntegerStringComparator();
var opts = new ColumnFamilyOptions()
.SetComparator(comparator);
var filename = Path.Combine(temp, "test.sst");
if (File.Exists(filename))
{
File.Delete(filename);
}
var sst = new SstFileWriter(ioOptions: opts);
sst.Open(filename);
sst.Add("111", "111");
sst.Add("1001", "1001"); // this order is only allowed using an integer comparator
sst.Finish();
}
// test write batch with index
{
var wbwi = new WriteBatchWithIndex(reservedBytes: 1024);
wbwi.Put("one", "un");
wbwi.Put("two", "deux");
var oneValueIn = Encoding.UTF8.GetBytes("one");
var oneValueOut = wbwi.Get("one");
Assert.Equal("un", oneValueOut);
using (var db = RocksDb.Open(options, path, columnFamilies))
{
var oneCombinedOut = wbwi.Get(db, "one");
var threeCombinedOut = wbwi.Get(db, "three");
Assert.Equal("un", oneCombinedOut);
Assert.Equal("tres", threeCombinedOut);
using (var wbIterator = wbwi.NewIterator(db.NewIterator()))
{
wbIterator.Seek("o");
Assert.True(wbIterator.Valid());
var itkey = wbIterator.StringKey();
Assert.Equal("one", itkey);
var itval = wbIterator.StringValue();
Assert.Equal("un", itval);
wbIterator.Next();
Assert.True(wbIterator.Valid());
itkey = wbIterator.StringKey();
Assert.Equal("three", itkey);
itval = wbIterator.StringValue();
Assert.Equal("tres", itval);
wbIterator.Next();
Assert.True(wbIterator.Valid());
itkey = wbIterator.StringKey();
Assert.Equal("two", itkey);
itval = wbIterator.StringValue();
Assert.Equal("deux", itval);
wbIterator.Next();
Assert.False(wbIterator.Valid());
}
db.Write(wbwi);
var oneDbOut = wbwi.Get("one");
Assert.Equal("un", oneDbOut);
}
}
// compact range
{
using (var db = RocksDb.Open(options, path, columnFamilies))
{
db.CompactRange("o", "tw");
}
}
}
/// <summary>
/// Provides access to and/or creates a RocksDb persistent key-value store.
/// </summary>
/// <param name="storeDirectory">
/// The directory containing the key-value store.
/// </param>
/// <param name="defaultColumnKeyTracked">
/// Whether the default column should be key-tracked.
/// This will create two columns for the same data,
/// one with just keys and the other with key and value.
/// </param>
/// <param name="additionalColumns">
/// The names of any additional column families in the key-value store.
/// If no additional column families are provided, all entries will be stored
/// in the default column.
/// Column families are analogous to tables in relational databases.
/// </param>
/// <param name="additionalKeyTrackedColumns">
/// The names of any additional column families in the key-value store that
/// should also be key-tracked. This will create two columns for the same data,
/// one with just keys and the other with key and value.
/// Column families are analogous to tables in relational databases.
/// </param>
/// <param name="readOnly">
/// Whether the database should be opened read-only. This prevents modifications and
/// creating unnecessary metadata files related to write sessions.
/// </param>
/// <param name="dropMismatchingColumns">
/// If a store already exists at the given directory, whether any columns that mismatch the the columns that were passed into the constructor
/// should be dropped. This will cause data loss and can only be applied in read-write mode.
/// </param>
/// <param name="rotateLogs">
/// Have RocksDb rotate logs, useful for debugging performance issues. It will rotate logs every 12 hours,
/// up to a maximum of 60 logs (i.e. 30 days). When the maximum amount of logs is reached, the oldest logs
/// are overwritten in a circular fashion.
///
/// Every time the RocksDb instance is open, the current log file is truncated, which means that if you
/// open the DB more than once in a 12 hour period, you will only have partial information.
/// </param>
public RocksDbStore(
string storeDirectory,
bool defaultColumnKeyTracked = false,
IEnumerable <string> additionalColumns = null,
IEnumerable <string> additionalKeyTrackedColumns = null,
bool readOnly = false,
bool dropMismatchingColumns = false,
bool rotateLogs = false)
{
m_storeDirectory = storeDirectory;
m_defaults.DbOptions = new DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true)
// The background compaction threads run in low priority, so they should not hamper the rest of
// the system. The number of cores in the system is what we want here according to official docs,
// and we are setting this to the number of logical processors, which may be higher.
.SetMaxBackgroundCompactions(Environment.ProcessorCount)
.SetMaxBackgroundFlushes(1)
.IncreaseParallelism(Environment.ProcessorCount / 2)
// Ensure we have performance statistics for profiling
.EnableStatistics();
// A small comment on things tested that did not work:
// * SetAllowMmapReads(true) and SetAllowMmapWrites(true) produce a dramatic performance drop
// * SetUseDirectReads(true) disables the OS cache, and although that's good for random point lookups,
// it produces a dramatic performance drop otherwise.
m_defaults.WriteOptions = new WriteOptions()
// Disable the write ahead log to reduce disk IO. The write ahead log
// is used to recover the store on crashes, so a crash will lose some writes.
// Writes will be made in-memory only until the write buffer size
// is reached and then they will be flushed to storage files.
.DisableWal(1)
// This option is off by default, but just making sure that the C# wrapper
// doesn't change anything. The idea is that the DB won't wait for fsync to
// return before acknowledging the write as successful. This affects
// correctness, because a write may be ACKd before it is actually on disk,
// but it is much faster.
.SetSync(false);
var blockBasedTableOptions = new BlockBasedTableOptions()
// Use a bloom filter to help reduce read amplification on point lookups. 10 bits per key yields a
// ~1% false positive rate as per the RocksDB documentation. This builds one filter per SST, which
// means its optimized for not having a key.
.SetFilterPolicy(BloomFilterPolicy.Create(10, false))
// Use a hash index in SST files to speed up point lookup.
.SetIndexType(BlockBasedTableIndexType.HashSearch)
// Whether to use the whole key or a prefix of it (obtained through the prefix extractor below).
// Since the prefix extractor is a no-op, better performance is achieved by turning this off (i.e.
// setting it to true).
.SetWholeKeyFiltering(true);
m_defaults.ColumnFamilyOptions = new ColumnFamilyOptions()
.SetBlockBasedTableFactory(blockBasedTableOptions)
.SetPrefixExtractor(SliceTransform.CreateNoOp());
if (rotateLogs)
{
// Maximum number of information log files
m_defaults.DbOptions.SetKeepLogFileNum(60);
// Do not rotate information logs based on file size
m_defaults.DbOptions.SetMaxLogFileSize(0);
// How long before we rotate the current information log file
m_defaults.DbOptions.SetLogFileTimeToRoll((ulong)TimeSpan.FromHours(12).Seconds);
}
m_columns = new Dictionary <string, ColumnFamilyInfo>();
additionalColumns = additionalColumns ?? CollectionUtilities.EmptyArray <string>();
additionalKeyTrackedColumns = additionalKeyTrackedColumns ?? CollectionUtilities.EmptyArray <string>();
// The columns that exist in the store on disk may not be in sync with the columns being passed into the constructor
HashSet <string> existingColumns;
try
{
existingColumns = new HashSet <string>(RocksDb.ListColumnFamilies(m_defaults.DbOptions, m_storeDirectory));
}
catch (RocksDbException)
{
// If there is no existing store, an exception will be thrown, ignore it
existingColumns = new HashSet <string>();
}
// In read-only mode, open all existing columns in the store without attempting to validate it against the expected column families
if (readOnly)
{
var columnFamilies = new ColumnFamilies();
foreach (var name in existingColumns)
{
columnFamilies.Add(name, m_defaults.ColumnFamilyOptions);
}
m_store = RocksDb.OpenReadOnly(m_defaults.DbOptions, m_storeDirectory, columnFamilies, errIfLogFileExists: false);
}
else
{
// For read-write mode, column families may be added, so set up column families schema
var columnsSchema = new HashSet <string>(additionalColumns);
// Default column
columnsSchema.Add(ColumnFamilies.DefaultName);
// For key-tracked column familiies, create two columns:
// 1: Normal column of { key : value }
// 2: Key-tracking column of { key : empty-value }
if (defaultColumnKeyTracked)
{
// To be robust to the RocksDB-selected default column name changing,
// just name the default column's key-tracking column KeyColumnSuffix
columnsSchema.Add(KeyColumnSuffix);
}
foreach (var name in additionalKeyTrackedColumns)
{
columnsSchema.Add(name);
columnsSchema.Add(name + KeyColumnSuffix);
}
// Figure out which columns are not part of the schema
var outsideSchemaColumns = new List <string>(existingColumns.Except(columnsSchema));
// RocksDB requires all columns in the store to be opened in read-write mode, so merge existing columns
// with the columns schema that was passed into the constructor
existingColumns.UnionWith(columnsSchema);
var columnFamilies = new ColumnFamilies();
foreach (var name in existingColumns)
{
columnFamilies.Add(name, m_defaults.ColumnFamilyOptions);
}
m_store = RocksDb.Open(m_defaults.DbOptions, m_storeDirectory, columnFamilies);
// Provide an opportunity to update the store to the new column family schema
if (dropMismatchingColumns)
{
foreach (var name in outsideSchemaColumns)
{
m_store.DropColumnFamily(name);
existingColumns.Remove(name);
}
}
}
var userFacingColumns = existingColumns.Where(name => !name.EndsWith(KeyColumnSuffix));
foreach (var name in userFacingColumns)
{
var isKeyTracked = existingColumns.Contains(name + KeyColumnSuffix);
m_columns.Add(name, new ColumnFamilyInfo()
{
Handle = m_store.GetColumnFamily(name),
UseKeyTracking = isKeyTracked,
KeyHandle = isKeyTracked ? m_store.GetColumnFamily(name + KeyColumnSuffix) : null,
});
}
m_columns.TryGetValue(ColumnFamilies.DefaultName, out m_defaultColumnFamilyInfo);
}
/// <summary>
/// Provides access to and/or creates a RocksDb persistent key-value store.
/// </summary>
public RocksDbStore(RocksDbStoreArguments arguments)
{
m_storeDirectory = arguments.StoreDirectory;
m_openBulkLoad = arguments.OpenBulkLoad;
m_defaults.DbOptions = new DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true)
// The background compaction threads run in low priority, so they should not hamper the rest of
// the system. The number of cores in the system is what we want here according to official docs,
// and we are setting this to the number of logical processors, which may be higher.
// See: https://github.com/facebook/rocksdb/wiki/RocksDB-Tuning-Guide#parallelism-options
#if !PLATFORM_OSX
.SetMaxBackgroundCompactions(Environment.ProcessorCount)
.SetMaxBackgroundFlushes(1)
#else
// The memtable uses significant chunks of available system memory on macOS, we increase the number
// of background flushing threads (low priority) and set the DB write buffer size. This allows for
// up to 128 MB in memtables across all column families before we flush to disk.
.SetMaxBackgroundCompactions(Environment.ProcessorCount / 4)
.SetMaxBackgroundFlushes(Environment.ProcessorCount / 4)
.SetDbWriteBufferSize(128 << 20)
#endif
.IncreaseParallelism(Environment.ProcessorCount / 2);
if (arguments.EnableStatistics)
{
m_defaults.DbOptions.EnableStatistics();
}
if (arguments.OpenBulkLoad)
{
m_defaults.DbOptions.PrepareForBulkLoad();
}
// Maximum number of information log files
if (arguments.RotateLogsNumFiles != null)
{
m_defaults.DbOptions.SetKeepLogFileNum(arguments.RotateLogsNumFiles.Value);
}
// Do not rotate information logs based on file size
if (arguments.RotateLogsMaxFileSizeBytes != null)
{
m_defaults.DbOptions.SetMaxLogFileSize(arguments.RotateLogsMaxFileSizeBytes.Value);
}
// How long before we rotate the current information log file
if (arguments.RotateLogsMaxAge != null)
{
m_defaults.DbOptions.SetLogFileTimeToRoll((ulong)arguments.RotateLogsMaxAge.Value.Seconds);
}
if (arguments.FastOpen)
{
// max_file_opening_threads is defaulted to 16, so no need to update here.
RocksDbSharp.Native.Instance.rocksdb_options_set_skip_stats_update_on_db_open(m_defaults.DbOptions.Handle, true);
}
if (arguments.DisableAutomaticCompactions)
{
m_defaults.DbOptions.SetDisableAutoCompactions(1);
}
// A small comment on things tested that did not work:
// * SetAllowMmapReads(true) and SetAllowMmapWrites(true) produce a dramatic performance drop
// * SetUseDirectReads(true) disables the OS cache, and although that's good for random point lookups,
// it produces a dramatic performance drop otherwise.
m_defaults.WriteOptions = new WriteOptions()
// Disable the write ahead log to reduce disk IO. The write ahead log
// is used to recover the store on crashes, so a crash will lose some writes.
// Writes will be made in-memory only until the write buffer size
// is reached and then they will be flushed to storage files.
.DisableWal(1)
// This option is off by default, but just making sure that the C# wrapper
// doesn't change anything. The idea is that the DB won't wait for fsync to
// return before acknowledging the write as successful. This affects
// correctness, because a write may be ACKd before it is actually on disk,
// but it is much faster.
.SetSync(false);
var blockBasedTableOptions = new BlockBasedTableOptions()
// Use a bloom filter to help reduce read amplification on point lookups. 10 bits per key yields a
// ~1% false positive rate as per the RocksDB documentation. This builds one filter per SST, which
// means its optimized for not having a key.
.SetFilterPolicy(BloomFilterPolicy.Create(10, false))
// Use a hash index in SST files to speed up point lookup.
.SetIndexType(BlockBasedTableIndexType.HashSearch)
// Whether to use the whole key or a prefix of it (obtained through the prefix extractor below).
// Since the prefix extractor is a no-op, better performance is achieved by turning this off (i.e.
// setting it to true).
.SetWholeKeyFiltering(true);
m_defaults.ColumnFamilyOptions = new ColumnFamilyOptions()
#if PLATFORM_OSX
// As advised by the official documentation, LZ4 is the preferred compression algorithm, our RocksDB
// dynamic library has been compiled to support this on macOS. Fallback to Snappy on other systems (default).
.SetCompression(CompressionTypeEnum.rocksdb_lz4_compression)
#endif
.SetBlockBasedTableFactory(blockBasedTableOptions)
.SetPrefixExtractor(SliceTransform.CreateNoOp());
m_columns = new Dictionary <string, ColumnFamilyInfo>();
// The columns that exist in the store on disk may not be in sync with the columns being passed into the constructor
HashSet <string> existingColumns;
try
{
existingColumns = new HashSet <string>(RocksDb.ListColumnFamilies(m_defaults.DbOptions, m_storeDirectory));
}
catch (RocksDbException)
{
// If there is no existing store, an exception will be thrown, ignore it
existingColumns = new HashSet <string>();
}
// In read-only mode, open all existing columns in the store without attempting to validate it against the expected column families
if (arguments.ReadOnly)
{
var columnFamilies = new ColumnFamilies();
foreach (var name in existingColumns)
{
columnFamilies.Add(name, m_defaults.ColumnFamilyOptions);
}
m_store = RocksDb.OpenReadOnly(m_defaults.DbOptions, m_storeDirectory, columnFamilies, errIfLogFileExists: false);
}
else
{
// For read-write mode, column families may be added, so set up column families schema
var additionalColumns = arguments.AdditionalColumns ?? CollectionUtilities.EmptyArray <string>();
var columnsSchema = new HashSet <string>(additionalColumns);
// Default column
columnsSchema.Add(ColumnFamilies.DefaultName);
// For key-tracked column familiies, create two columns:
// 1: Normal column of { key : value }
// 2: Key-tracking column of { key : empty-value }
if (arguments.DefaultColumnKeyTracked)
{
// To be robust to the RocksDB-selected default column name changing,
// just name the default column's key-tracking column KeyColumnSuffix
columnsSchema.Add(KeyColumnSuffix);
}
var additionalKeyTrackedColumns = arguments.AdditionalKeyTrackedColumns ?? CollectionUtilities.EmptyArray <string>();
foreach (var name in additionalKeyTrackedColumns)
{
columnsSchema.Add(name);
columnsSchema.Add(name + KeyColumnSuffix);
}
// Figure out which columns are not part of the schema
var outsideSchemaColumns = new List <string>(existingColumns.Except(columnsSchema));
// RocksDB requires all columns in the store to be opened in read-write mode, so merge existing columns
// with the columns schema that was passed into the constructor
existingColumns.UnionWith(columnsSchema);
var columnFamilies = new ColumnFamilies();
foreach (var name in existingColumns)
{
columnFamilies.Add(name, m_defaults.ColumnFamilyOptions);
}
m_store = RocksDb.Open(m_defaults.DbOptions, m_storeDirectory, columnFamilies);
// Provide an opportunity to update the store to the new column family schema
if (arguments.DropMismatchingColumns)
{
foreach (var name in outsideSchemaColumns)
{
m_store.DropColumnFamily(name);
existingColumns.Remove(name);
}
}
}
var userFacingColumns = existingColumns.Where(name => !name.EndsWith(KeyColumnSuffix));
foreach (var name in userFacingColumns)
{
var isKeyTracked = existingColumns.Contains(name + KeyColumnSuffix);
m_columns.Add(name, new ColumnFamilyInfo()
{
Handle = m_store.GetColumnFamily(name),
UseKeyTracking = isKeyTracked,
KeyHandle = isKeyTracked ? m_store.GetColumnFamily(name + KeyColumnSuffix) : null,
});
}
m_columns.TryGetValue(ColumnFamilies.DefaultName, out m_defaultColumnFamilyInfo);
}
public void FunctionalTest()
{
string temp = Path.GetTempPath();
var testdir = Path.Combine(temp, "functional_test");
var testdb = Path.Combine(testdir, "main");
var testcp = Path.Combine(testdir, "cp");
var path = Environment.ExpandEnvironmentVariables(testdb);
var cppath = Environment.ExpandEnvironmentVariables(testcp);
if (Directory.Exists(testdir))
{
Directory.Delete(testdir, true);
}
Directory.CreateDirectory(testdir);
var options = new DbOptions()
.SetCreateIfMissing(true)
.EnableStatistics();
// Using standard open
using (var db = RocksDb.Open(options, path))
{
// With strings
string value = db.Get("key");
db.Put("key", "value");
Assert.Equal("value", db.Get("key"));
Assert.Null(db.Get("non-existent-key"));
db.Remove("key");
Assert.Null(db.Get("value"));
// With bytes
db.Put(Encoding.UTF8.GetBytes("key"), Encoding.UTF8.GetBytes("value"));
Assert.True(BinaryComparer.Default.Equals(Encoding.UTF8.GetBytes("value"), db.Get(Encoding.UTF8.GetBytes("key"))));
// non-existent kiey
Assert.Null(db.Get(new byte[] { 0, 1, 2 }));
db.Remove(Encoding.UTF8.GetBytes("key"));
Assert.Null(db.Get(Encoding.UTF8.GetBytes("key")));
db.Put(Encoding.UTF8.GetBytes("key"), new byte[] { 0, 1, 2, 3, 4, 5, 6, 7 });
// With buffers
var buffer = new byte[100];
long length = db.Get(Encoding.UTF8.GetBytes("key"), buffer, 0, buffer.Length);
Assert.Equal(8, length);
Assert.Equal(new byte[] { 0, 1, 2, 3, 4, 5, 6, 7 }, buffer.Take((int)length).ToList());
buffer = new byte[5];
length = db.Get(Encoding.UTF8.GetBytes("key"), buffer, 0, buffer.Length);
Assert.Equal(8, length);
Assert.Equal(new byte[] { 0, 1, 2, 3, 4 }, buffer.Take((int)Math.Min(buffer.Length, length)));
length = db.Get(Encoding.UTF8.GetBytes("bogus"), buffer, 0, buffer.Length);
Assert.Equal(-1, length);
// Write batches
// With strings
using (WriteBatch batch = new WriteBatch()
.Put("one", "uno")
.Put("two", "deuce")
.Put("two", "dos")
.Put("three", "tres"))
{
db.Write(batch);
}
Assert.Equal("uno", db.Get("one"));
// With save point
using (WriteBatch batch = new WriteBatch())
{
batch
.Put("hearts", "red")
.Put("diamonds", "red");
batch.SetSavePoint();
batch
.Put("clubs", "black");
batch.SetSavePoint();
batch
.Put("spades", "black");
batch.RollbackToSavePoint();
db.Write(batch);
}
Assert.Equal("red", db.Get("diamonds"));
Assert.Equal("black", db.Get("clubs"));
Assert.Null(db.Get("spades"));
// Save a checkpoint
using (var cp = db.Checkpoint())
{
cp.Save(cppath);
}
// With bytes
var utf8 = Encoding.UTF8;
using (WriteBatch batch = new WriteBatch()
.Put(utf8.GetBytes("four"), new byte[] { 4, 4, 4 })
.Put(utf8.GetBytes("five"), new byte[] { 5, 5, 5 }))
{
db.Write(batch);
}
Assert.True(BinaryComparer.Default.Equals(new byte[] { 4, 4, 4 }, db.Get(utf8.GetBytes("four"))));
// Snapshots
using (var snapshot = db.CreateSnapshot())
{
var before = db.Get("one");
db.Put("one", "1");
var useSnapshot = new ReadOptions()
.SetSnapshot(snapshot);
// the database value was written
Assert.Equal("1", db.Get("one"));
// but the snapshot still sees the old version
var after = db.Get("one", readOptions: useSnapshot);
Assert.Equal(before, after);
}
var two = db.Get("two");
Assert.Equal("dos", two);
// Iterators
using (var iterator = db.NewIterator(
readOptions: new ReadOptions()
.SetIterateUpperBound("t")
))
{
iterator.Seek("k");
Assert.True(iterator.Valid());
Assert.Equal("key", iterator.StringKey());
iterator.Next();
Assert.True(iterator.Valid());
Assert.Equal("one", iterator.StringKey());
Assert.Equal("1", iterator.StringValue());
iterator.Next();
Assert.False(iterator.Valid());
}
// MultiGet
var multiGetResult = db.MultiGet(new[] { "two", "three", "nine" });
Assert.Equal(
expected: new[]
{
new KeyValuePair <string, string>("two", "dos"),
new KeyValuePair <string, string>("three", "tres"),
new KeyValuePair <string, string>("nine", null)
},
actual: multiGetResult
);
}
// Test reading checkpointed db
using (var cpdb = RocksDb.Open(options, cppath))
{
Assert.Equal("red", cpdb.Get("diamonds"));
Assert.Equal("black", cpdb.Get("clubs"));
Assert.Null(cpdb.Get("spades"));
// Checkpoint occurred before these changes:
Assert.Null(cpdb.Get("four"));
}
// Test with column families
var optionsCf = new DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true);
var columnFamilies = new ColumnFamilies
{
{ "reverse", new ColumnFamilyOptions() },
};
using (var db = RocksDb.Open(optionsCf, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
db.Put("one", "uno");
db.Put("two", "dos");
db.Put("three", "tres");
db.Put("uno", "one", cf: reverse);
db.Put("dos", "two", cf: reverse);
db.Put("tres", "three", cf: reverse);
}
// Test Cf Delete
using (var db = RocksDb.Open(optionsCf, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
db.Put("cuatro", "four", cf: reverse);
db.Put("cinco", "five", cf: reverse);
Assert.Equal("four", db.Get("cuatro", cf: reverse));
Assert.Equal("five", db.Get("cinco", cf: reverse));
byte[] keyBytes = Encoding.UTF8.GetBytes("cuatro");
db.Remove(keyBytes, reverse);
db.Remove("cinco", reverse);
Assert.Null(db.Get("cuatro", cf: reverse));
Assert.Null(db.Get("cinco", cf: reverse));
}
// Test list
{
var list = RocksDb.ListColumnFamilies(optionsCf, path);
Assert.Equal(new[] { "default", "reverse" }, list.ToArray());
}
// Test reopen with column families
using (var db = RocksDb.Open(optionsCf, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
Assert.Equal("uno", db.Get("one"));
Assert.Equal("one", db.Get("uno", cf: reverse));
Assert.Null(db.Get("uno"));
Assert.Null(db.Get("one", cf: reverse));
}
// Test dropping and creating column family
using (var db = RocksDb.Open(options, path, columnFamilies))
{
db.DropColumnFamily("reverse");
var reverse = db.CreateColumnFamily(new ColumnFamilyOptions(), "reverse");
Assert.Null(db.Get("uno", cf: reverse));
db.Put("red", "rouge", cf: reverse);
Assert.Equal("rouge", db.Get("red", cf: reverse));
}
// Test reopen after drop and create
using (var db = RocksDb.Open(options, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
Assert.Null(db.Get("uno", cf: reverse));
Assert.Equal("rouge", db.Get("red", cf: reverse));
}
// Test read only
using (var db = RocksDb.OpenReadOnly(options, path, columnFamilies, false))
{
Assert.Equal("uno", db.Get("one"));
}
// Test SstFileWriter
{
using (var writer = new SstFileWriter())
{
}
var envOpts = new EnvOptions();
var ioOpts = new ColumnFamilyOptions();
using (var sst = new SstFileWriter(envOpts, ioOpts))
{
var filename = Path.Combine(temp, "test.sst");
if (File.Exists(filename))
{
File.Delete(filename);
}
sst.Open(filename);
sst.Add("four", "quatro");
sst.Add("one", "uno");
sst.Add("two", "dos");
sst.Finish();
using (var db = RocksDb.Open(options, path, columnFamilies))
{
Assert.NotEqual("four", db.Get("four"));
var ingestOptions = new IngestExternalFileOptions()
.SetMoveFiles(true);
db.IngestExternalFiles(new string[] { filename }, ingestOptions);
Assert.Equal("quatro", db.Get("four"));
}
}
}
// test comparator
unsafe {
var opts = new ColumnFamilyOptions()
.SetComparator(new IntegerStringComparator());
var filename = Path.Combine(temp, "test.sst");
if (File.Exists(filename))
{
File.Delete(filename);
}
using (var sst = new SstFileWriter(ioOptions: opts))
{
sst.Open(filename);
sst.Add("111", "111");
sst.Add("1001", "1001"); // this order is only allowed using an integer comparator
sst.Finish();
}
}
// test write batch with index
{
var wbwi = new WriteBatchWithIndex(reservedBytes: 1024);
wbwi.Put("one", "un");
wbwi.Put("two", "deux");
var oneValueIn = Encoding.UTF8.GetBytes("one");
var oneValueOut = wbwi.Get("one");
Assert.Equal("un", oneValueOut);
using (var db = RocksDb.Open(options, path, columnFamilies))
{
var oneCombinedOut = wbwi.Get(db, "one");
var threeCombinedOut = wbwi.Get(db, "three");
Assert.Equal("un", oneCombinedOut);
Assert.Equal("tres", threeCombinedOut);
using (var wbIterator = wbwi.NewIterator(db.NewIterator()))
{
wbIterator.Seek("o");
Assert.True(wbIterator.Valid());
var itkey = wbIterator.StringKey();
Assert.Equal("one", itkey);
var itval = wbIterator.StringValue();
Assert.Equal("un", itval);
wbIterator.Next();
Assert.True(wbIterator.Valid());
itkey = wbIterator.StringKey();
Assert.Equal("three", itkey);
itval = wbIterator.StringValue();
Assert.Equal("tres", itval);
wbIterator.Next();
Assert.True(wbIterator.Valid());
itkey = wbIterator.StringKey();
Assert.Equal("two", itkey);
itval = wbIterator.StringValue();
Assert.Equal("deux", itval);
wbIterator.Next();
Assert.False(wbIterator.Valid());
}
db.Write(wbwi);
var oneDbOut = wbwi.Get("one");
Assert.Equal("un", oneDbOut);
}
}
// compact range
{
using (var db = RocksDb.Open(options, path, columnFamilies))
{
db.CompactRange("o", "tw");
}
}
// Smoke test various options
{
var dbname = "test-options";
if (Directory.Exists(dbname))
{
Directory.Delete(dbname, true);
}
var optsTest = (DbOptions) new RocksDbSharp.DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true)
.SetBlockBasedTableFactory(new BlockBasedTableOptions().SetBlockCache(Cache.CreateLru(1024 * 1024)));
GC.Collect();
using (var db = RocksDbSharp.RocksDb.Open(optsTest, dbname))
{
}
if (Directory.Exists(dbname))
{
Directory.Delete(dbname, true);
}
}
// Smoke test OpenWithTtl
{
var dbname = "test-with-ttl";
if (Directory.Exists(dbname))
{
Directory.Delete(dbname, true);
}
var optsTest = (DbOptions) new RocksDbSharp.DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true);
using (var db = RocksDbSharp.RocksDb.OpenWithTtl(optsTest, dbname, 1))
{
}
if (Directory.Exists(dbname))
{
Directory.Delete(dbname, true);
}
}
// Smoke test MergeOperator
{
var dbname = "test-merge-operator";
if (Directory.Exists(dbname))
{
Directory.Delete(dbname, true);
}
var optsTest = (DbOptions) new RocksDbSharp.DbOptions()
.SetCreateIfMissing(true)
.SetMergeOperator(MergeOperators.Create(
name: "test-merge-operator",
partialMerge: (key, keyLength, operandsList, operandsListLength, numOperands, success, newValueLength) => IntPtr.Zero,
fullMerge: (key, keyLength, existingValue, existingValueLength, operandsList, operandsListLength, numOperands, success, newValueLength) => IntPtr.Zero,
deleteValue: (value, valueLength) => { }
));
GC.Collect();
using (var db = RocksDbSharp.RocksDb.Open(optsTest, dbname))
{
}
if (Directory.Exists(dbname))
{
Directory.Delete(dbname, true);
}
}
// Test that GC does not cause access violation on Comparers
{
var dbname = "test-av-error";
if (Directory.Exists(dbname))
{
Directory.Delete(dbname, true);
}
options = new RocksDbSharp.DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true);
var sc = new RocksDbSharp.StringComparator(StringComparer.InvariantCultureIgnoreCase);
columnFamilies = new RocksDbSharp.ColumnFamilies
{
{ "cf1", new RocksDbSharp.ColumnFamilyOptions()
.SetComparator(sc) },
};
GC.Collect();
using (var db = RocksDbSharp.RocksDb.Open(options, dbname, columnFamilies))
{
}
if (Directory.Exists(dbname))
{
Directory.Delete(dbname, true);
}
}
}
/// <summary>
/// Provides access to and/or creates a RocksDb persistent key-value store.
/// </summary>
/// <param name="storeDirectory">
/// The directory containing the key-value store.
/// </param>
/// <param name="defaultColumnKeyTracked">
/// Whether the default column should be key-tracked.
/// This will create two columns for the same data,
/// one with just keys and the other with key and value.
/// </param>
/// <param name="additionalColumns">
/// The names of any additional column families in the key-value store.
/// If no additional column families are provided, all entries will be stored
/// in the default column.
/// Column families are analogous to tables in relational databases.
/// </param>
/// <param name="additionalKeyTrackedColumns">
/// The names of any additional column families in the key-value store that
/// should also be key-tracked. This will create two columns for the same data,
/// one with just keys and the other with key and value.
/// Column families are analogous to tables in relational databases.
/// </param>
/// <param name="readOnly">
/// Whether the database should be opened read-only. This prevents modifications and
/// creating unnecessary metadata files related to write sessions.
/// </param>
/// <param name="dropMismatchingColumns">
/// If a store already exists at the given directory, whether any columns that mismatch the the columns that were passed into the constructor
/// should be dropped. This will cause data loss and can only be applied in read-write mode.
/// </param>
public RocksDbStore(
string storeDirectory,
bool defaultColumnKeyTracked = false,
IEnumerable <string> additionalColumns = null,
IEnumerable <string> additionalKeyTrackedColumns = null,
bool readOnly = false,
bool dropMismatchingColumns = false)
{
m_storeDirectory = storeDirectory;
m_defaults.DbOptions = new DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true);
// Disable the write ahead log to reduce disk IO. The write ahead log
// is used to recover the store on crashes, so a crash will lose some writes.
// Writes will be made in-memory only until the write buffer size
// is reached and then they will be flushed to storage files.
m_defaults.WriteOptions = new WriteOptions().DisableWal(1);
m_defaults.ColumnFamilyOptions = new ColumnFamilyOptions();
m_columns = new Dictionary <string, ColumnFamilyInfo>();
additionalColumns = additionalColumns ?? CollectionUtilities.EmptyArray <string>();
additionalKeyTrackedColumns = additionalKeyTrackedColumns ?? CollectionUtilities.EmptyArray <string>();
// The columns that exist in the store on disk may not be in sync with the columns being passed into the constructor
HashSet <string> existingColumns;
try
{
existingColumns = new HashSet <string>(RocksDb.ListColumnFamilies(m_defaults.DbOptions, m_storeDirectory));
}
catch (RocksDbException)
{
// If there is no existing store, an exception will be thrown, ignore it
existingColumns = new HashSet <string>();
}
// In read-only mode, open all existing columns in the store without attempting to validate it against the expected column families
if (readOnly)
{
var columnFamilies = new ColumnFamilies();
foreach (var name in existingColumns)
{
columnFamilies.Add(name, m_defaults.ColumnFamilyOptions);
}
m_store = RocksDb.OpenReadOnly(m_defaults.DbOptions, m_storeDirectory, columnFamilies, errIfLogFileExists: false);
}
else
{
// For read-write mode, column families may be added, so set up column families schema
var columnsSchema = new HashSet <string>(additionalColumns);
// Default column
columnsSchema.Add(ColumnFamilies.DefaultName);
// For key-tracked column familiies, create two columns:
// 1: Normal column of { key : value }
// 2: Key-tracking column of { key : empty-value }
if (defaultColumnKeyTracked)
{
// To be robust to the RocksDB-selected default column name changing,
// just name the default column's key-tracking column KeyColumnSuffix
columnsSchema.Add(KeyColumnSuffix);
}
foreach (var name in additionalKeyTrackedColumns)
{
columnsSchema.Add(name);
columnsSchema.Add(name + KeyColumnSuffix);
}
// Figure out which columns are not part of the schema
var outsideSchemaColumns = new List <string>(existingColumns.Except(columnsSchema));
// RocksDB requires all columns in the store to be opened in read-write mode, so merge existing columns
// with the columns schema that was passed into the constructor
existingColumns.UnionWith(columnsSchema);
var columnFamilies = new ColumnFamilies();
foreach (var name in existingColumns)
{
columnFamilies.Add(name, m_defaults.ColumnFamilyOptions);
}
m_store = RocksDb.Open(m_defaults.DbOptions, m_storeDirectory, columnFamilies);
// Provide an opportunity to update the store to the new column family schema
if (dropMismatchingColumns)
{
foreach (var name in outsideSchemaColumns)
{
m_store.DropColumnFamily(name);
existingColumns.Remove(name);
}
}
}
var userFacingColumns = existingColumns.Where(name => !name.EndsWith(KeyColumnSuffix));
foreach (var name in userFacingColumns)
{
var isKeyTracked = existingColumns.Contains(name + KeyColumnSuffix);
m_columns.Add(name, new ColumnFamilyInfo()
{
Handle = m_store.GetColumnFamily(name),
UseKeyTracking = isKeyTracked,
KeyHandle = isKeyTracked ? m_store.GetColumnFamily(name + KeyColumnSuffix) : null,
});
}
m_columns.TryGetValue(ColumnFamilies.DefaultName, out m_defaultColumnFamilyInfo);
}
public void FunctionalTest()
{
string temp = Path.GetTempPath();
var testdb = Path.Combine(temp, "functional_test");
string path = Environment.ExpandEnvironmentVariables(testdb);
if (Directory.Exists(testdb))
{
Directory.Delete(testdb, true);
}
var options = new DbOptions()
.SetCreateIfMissing(true)
.EnableStatistics();
// Using standard open
using (var db = RocksDb.Open(options, path))
{
// With strings
string value = db.Get("key");
db.Put("key", "value");
Assert.AreEqual("value", db.Get("key"));
Assert.IsNull(db.Get("non-existent-key"));
db.Remove("key");
Assert.IsNull(db.Get("value"));
// With bytes
db.Put(Encoding.UTF8.GetBytes("key"), Encoding.UTF8.GetBytes("value"));
Assert.IsTrue(BinaryComparer.Default.Equals(Encoding.UTF8.GetBytes("value"), db.Get(Encoding.UTF8.GetBytes("key"))));
// non-existent kiey
Assert.IsNull(db.Get(new byte[] { 0, 1, 2 }));
db.Remove(Encoding.UTF8.GetBytes("key"));
Assert.IsNull(db.Get(Encoding.UTF8.GetBytes("key")));
db.Put(Encoding.UTF8.GetBytes("key"), new byte[] { 0, 1, 2, 3, 4, 5, 6, 7 });
// With buffers
var buffer = new byte[100];
long length = db.Get(Encoding.UTF8.GetBytes("key"), buffer, 0, buffer.Length);
Assert.AreEqual(8, length);
CollectionAssert.AreEqual(new byte[] { 0, 1, 2, 3, 4, 5, 6, 7 }, buffer.Take((int)length).ToList());
// Write batches
// With strings
using (WriteBatch batch = new WriteBatch()
.Put("one", "uno")
.Put("two", "deuce")
.Put("two", "dos")
.Put("three", "tres"))
{
db.Write(batch);
}
Assert.AreEqual("uno", db.Get("one"));
// With bytes
var utf8 = Encoding.UTF8;
using (WriteBatch batch = new WriteBatch()
.Put(utf8.GetBytes("four"), new byte[] { 4, 4, 4 })
.Put(utf8.GetBytes("five"), new byte[] { 5, 5, 5 }))
{
db.Write(batch);
}
Assert.IsTrue(BinaryComparer.Default.Equals(new byte[] { 4, 4, 4 }, db.Get(utf8.GetBytes("four"))));
// Snapshots
using (var snapshot = db.CreateSnapshot())
{
var before = db.Get("one");
db.Put("one", "1");
var useSnapshot = new ReadOptions()
.SetSnapshot(snapshot);
// the database value was written
Assert.AreEqual("1", db.Get("one"));
// but the snapshot still sees the old version
var after = db.Get("one", readOptions: useSnapshot);
Assert.AreEqual(before, after);
}
var two = db.Get("two");
Assert.AreEqual("dos", two);
// Iterators
using (var iterator = db.NewIterator(
readOptions: new ReadOptions()
.SetIterateUpperBound("t")
))
{
iterator.Seek("k");
Assert.IsTrue(iterator.Valid());
Assert.AreEqual("key", iterator.StringKey());
iterator.Next();
Assert.IsTrue(iterator.Valid());
Assert.AreEqual("one", iterator.StringKey());
Assert.AreEqual("1", iterator.StringValue());
iterator.Next();
Assert.IsFalse(iterator.Valid());
}
}
// Test with column families
var optionsCf = new DbOptions()
.SetCreateIfMissing(true)
.SetCreateMissingColumnFamilies(true);
var columnFamilies = new ColumnFamilies
{
{ "reverse", new ColumnFamilyOptions() },
};
using (var db = RocksDb.Open(optionsCf, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
db.Put("one", "uno");
db.Put("two", "dos");
db.Put("three", "tres");
db.Put("uno", "one", cf: reverse);
db.Put("dos", "two", cf: reverse);
db.Put("tres", "three", cf: reverse);
}
// Test reopen with column families
using (var db = RocksDb.Open(optionsCf, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
Assert.AreEqual("uno", db.Get("one"));
Assert.AreEqual("one", db.Get("uno", cf: reverse));
Assert.IsNull(db.Get("uno"));
Assert.IsNull(db.Get("one", cf: reverse));
}
// Test dropping and creating column family
using (var db = RocksDb.Open(options, path, columnFamilies))
{
db.DropColumnFamily("reverse");
var reverse = db.CreateColumnFamily(new ColumnFamilyOptions(), "reverse");
Assert.IsNull(db.Get("uno", cf: reverse));
db.Put("red", "rouge", cf: reverse);
Assert.AreEqual("rouge", db.Get("red", cf: reverse));
}
// Test reopen after drop and create
using (var db = RocksDb.Open(options, path, columnFamilies))
{
var reverse = db.GetColumnFamily("reverse");
Assert.IsNull(db.Get("uno", cf: reverse));
Assert.AreEqual("rouge", db.Get("red", cf: reverse));
}
// Test read only
using (var db = RocksDb.OpenReadOnly(options, path, columnFamilies, false))
{
Assert.AreEqual("uno", db.Get("one"));
}
}
public static RocksDb OpenReadOnlyDb(string path)
{
var columnFamilies = GetColumnFamilies(path);
return(RocksDb.OpenReadOnly(new DbOptions(), path, columnFamilies, false));
}