public void Snapshot()
{
// modify db
var writeOptions = Native.leveldb_writeoptions_create();
Native.leveldb_put(Database, writeOptions, "key1", "value1");
Native.leveldb_writeoptions_destroy(writeOptions);
// create snapshot
var snapshot = Native.leveldb_create_snapshot(Database);
// modify db again
writeOptions = Native.leveldb_writeoptions_create();
Native.leveldb_put(Database, writeOptions, "key2", "value2");
Native.leveldb_writeoptions_destroy(writeOptions);
// read from snapshot
var readOptions = Native.leveldb_readoptions_create();
Native.leveldb_readoptions_set_snapshot(readOptions, snapshot);
var val1 = Native.leveldb_get(Database, readOptions, "key1");
Assert.AreEqual("value1", val1);
var val2 = Native.leveldb_get(Database, readOptions, "key2");
Assert.IsNull(val2);
Native.leveldb_readoptions_destroy(readOptions);
// release snapshot
Native.leveldb_release_snapshot(Database, snapshot);
snapshot = IntPtr.Zero;
}
public void WriteBatch()
{
var writeOptions = Native.leveldb_writeoptions_create();
Native.leveldb_put(Database, writeOptions, "key1", "value1");
var writeBatch = Native.leveldb_writebatch_create();
Native.leveldb_writebatch_delete(writeBatch, "key1");
Native.leveldb_writebatch_put(writeBatch, "key2", "value2");
Native.leveldb_write(Database, writeOptions, writeBatch);
var readOptions = Native.leveldb_readoptions_create();
var value1 = Native.leveldb_get(Database, readOptions, "key1");
Assert.IsNull(value1);
var value2 = Native.leveldb_get(Database, readOptions, "key2");
Assert.AreEqual("value2", value2);
Native.leveldb_writebatch_delete(writeBatch, "key2");
Native.leveldb_writebatch_clear(writeBatch);
Native.leveldb_write(Database, writeOptions, writeBatch);
value2 = Native.leveldb_get(Database, readOptions, "key2");
Assert.AreEqual("value2", value2);
Native.leveldb_writebatch_destroy(writeBatch);
Native.leveldb_writeoptions_destroy(writeOptions);
Native.leveldb_writeoptions_destroy(readOptions);
}
public void Enumerator()
{
var writeOptions = Native.leveldb_writeoptions_create();
Native.leveldb_put(Database, writeOptions, "key1", "value1");
Native.leveldb_put(Database, writeOptions, "key2", "value2");
Native.leveldb_put(Database, writeOptions, "key3", "value3");
var entries = new List <KeyValuePair <string, string> >();
var readOptions = Native.leveldb_readoptions_create();
IntPtr iter = Native.leveldb_create_iterator(Database, readOptions);
for (Native.leveldb_iter_seek_to_first(iter);
(int)Native.leveldb_iter_valid(iter) != 0;
Native.leveldb_iter_next(iter))
{
string key = Native.leveldb_iter_key(iter);
string value = Native.leveldb_iter_value(iter);
var entry = new KeyValuePair <string, string>(key, value);
entries.Add(entry);
}
Native.leveldb_iter_destroy(iter);
Native.leveldb_readoptions_destroy(readOptions);
Assert.AreEqual(3, entries.Count);
Assert.AreEqual("key1", entries[0].Key);
Assert.AreEqual("value1", entries[0].Value);
Assert.AreEqual("key2", entries[1].Key);
Assert.AreEqual("value2", entries[1].Value);
Assert.AreEqual("key3", entries[2].Key);
Assert.AreEqual("value3", entries[2].Value);
Native.leveldb_writeoptions_destroy(writeOptions);
}
public void Delete()
{
var writeOptions = Native.leveldb_writeoptions_create();
Native.leveldb_put(Database, writeOptions, "key1", "value1");
var readOptions = Native.leveldb_readoptions_create();
var value1 = Native.leveldb_get(Database, readOptions, "key1");
Assert.AreEqual("value1", value1);
Native.leveldb_delete(Database, writeOptions, "key1");
value1 = Native.leveldb_get(Database, readOptions, "key1");
Assert.IsNull(value1);
Native.leveldb_writeoptions_destroy(writeOptions);
Native.leveldb_readoptions_destroy(readOptions);
}
