@Test
    public void getApproximateKeysInRangeTest() {
        final List<KVEntry> entries = Lists.newArrayList();
        for (int i = 0; i < 10000; i++) {
            entries.add(new KVEntry(makeKey("approximate_test" + i), makeValue("approximate_test_value")));
        }
        this.kvStore.put(entries, null);

        long approximateKeys = this.kvStore.getApproximateKeysInRange(makeKey("approximate_test" + 9999), null);
        assertEquals(1, approximateKeys);
        approximateKeys = this.kvStore.getApproximateKeysInRange(null, makeKey("approximate_test" + 9999));
        assertEquals(10000, approximateKeys);
        approximateKeys = this.kvStore.getApproximateKeysInRange(makeKey("approximate_test" + 9990),
            makeKey("approximate_test" + 9999));
        assertEquals(10, approximateKeys);
    }
Test method: {@link RocksRawKVStore#delete(List, KVStoreClosure)}
jraft-rheakv/rheakv-core/src/test/java/com/alipay/sofa/jraft/rhea/storage/rocksdb/RocksKVStoreTest.java