blob: 0b21925e2776c6503e0f39008d81833665661585 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
|
#pragma once
#include "Api.h"
#include "IStorageBackend.h"
#include <sqlite3.h>
#include <string>
#include <vector>
/**
* @file SqliteBackend.h
* @brief IStorageBackend implementation backed by an in-process SQLite database.
*
* SQLite schema:
*
* kv(hash TEXT PRIMARY KEY, value BLOB NOT NULL)
* — content-addressed store; key is the SHA256 hex digest of value.
*
* relation_index(path TEXT NOT NULL, tuple_hash TEXT NOT NULL,
* UNIQUE(path, tuple_hash))
* — maps a relation's logical path to the ordered set of tuple hashes
* it contains. Corresponds to Sakura's per-relation B+ tree of
* tuple hashes stored in the physical layer.
*/
namespace nt
{
/**
* @class SqliteBackend
* @brief IStorageBackend that persists data in a SQLite database.
*
* Constructed with a file path or ":memory:" for an in-process database.
* All KV values are opaque blobs; callers are responsible for serialization
* (see TupleCodec).
*/
class NT_API SqliteBackend : public IStorageBackend
{
public:
/**
* @brief Opens (or creates) a SQLite database at @p path.
* @param path File path, or ":memory:" for an in-process database.
* @throws std::runtime_error if the database cannot be opened.
*/
explicit SqliteBackend(const std::string& path = ":memory:");
~SqliteBackend() override;
std::string Put(std::vector<uint8_t> value) override;
std::optional<std::vector<uint8_t>> Get(const std::string& hash) override;
void LinkTuple(const std::vector<std::string>& relation_path,
const std::string& tuple_hash) override;
std::vector<std::string> TupleHashes(const std::vector<std::string>& relation_path,
std::size_t offset,
std::size_t limit) override;
private:
sqlite3* db_ = nullptr;
static std::string PathKey(const std::vector<std::string>& path);
};
}
|
