uqa-engine 0.5.0

Engine: schema-aware table store, catalog restore, transactions
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
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135

//
// Unified Query Algebra
//
// Copyright (c) 2023-2026 Cognica, Inc.
//

//! Session-owned resources must expire without waiting for another database to open.

use super::*;

fn persistent(provider: usize, path: &std::path::Path) -> Engine {
    match provider {
        0 => Engine::open(path).unwrap(),
        1 => Engine::from_persistent_provider(Arc::new(
            uqa_storage_sqlite::SQLiteKeyValueStorage::open(path).unwrap(),
        ))
        .unwrap(),
        2 => Engine::from_persistent_provider(Arc::new(
            uqa_storage_redb::RedbStorage::open(path).unwrap(),
        ))
        .unwrap(),
        3 => native_storage::legacy_engine(path),
        _ => unreachable!(),
    }
}

fn assert_released(engine: Engine) {
    let provider = Arc::downgrade(engine.storage.provider.as_ref().unwrap());
    let backend = Arc::downgrade(engine.storage.backend.as_ref().unwrap());
    let session = Arc::downgrade(&engine.session);
    let catalog = Arc::downgrade(&engine.durable);
    let tables = Arc::downgrade(&engine.storage.tables);
    let statistics = Arc::downgrade(&engine.statistics);
    let notifications = Arc::downgrade(&engine.notification_hub);
    let locks = Arc::downgrade(&engine.row_locks);
    drop(engine);
    assert!(
        session.upgrade().is_none(),
        "session survived its last owner"
    );
    assert!(
        catalog.upgrade().is_none(),
        "catalog survived its last owner"
    );
    assert!(
        tables.upgrade().is_none(),
        "tables survived their last owner"
    );
    assert!(
        statistics.upgrade().is_none(),
        "maintenance survived its last owner"
    );
    assert!(
        notifications.upgrade().is_none(),
        "notifications survived their last owner"
    );
    assert!(locks.upgrade().is_none(), "locks survived their last owner");
    assert!(
        backend.upgrade().is_none(),
        "backend survived its last owner"
    );
    assert!(
        provider.upgrade().is_none(),
        "provider survived its last owner"
    );
}

#[test]
fn dropping_unfinished_transactions_releases_fixed_graph_and_cursor_snapshots() {
    for provider in 0..4 {
        let directory = tempfile::tempdir().unwrap();
        let engine = persistent(provider, &directory.path().join("unfinished.db"));
        engine
            .sql(
                "CREATE TABLE t(id integer); INSERT INTO t VALUES (1), (2)",
                &[],
            )
            .unwrap();
        engine.create_graph("retained").unwrap();
        engine.sql("BEGIN ISOLATION LEVEL REPEATABLE READ; SELECT * FROM t; SAVEPOINT nested; DECLARE pending CURSOR FOR SELECT * FROM t; FETCH 1 FROM pending", &[]).unwrap();
        assert_released(engine);
    }
}

#[test]
fn dropping_holdable_cursors_releases_their_committed_snapshot() {
    for provider in 0..4 {
        let directory = tempfile::tempdir().unwrap();
        let engine = persistent(provider, &directory.path().join("holdable.db"));
        engine
            .sql(
                "CREATE TABLE t(id integer); INSERT INTO t VALUES (1), (2)",
                &[],
            )
            .unwrap();
        engine.create_graph("retained").unwrap();
        engine.sql("BEGIN; DECLARE held CURSOR WITH HOLD FOR SELECT * FROM t; FETCH 1 FROM held; COMMIT", &[]).unwrap();
        assert_released(engine);
    }
}

#[test]
fn dropping_session_deadlines_releases_their_termination_handles() {
    for provider in 0..4 {
        for transaction in [false, true] {
            let directory = tempfile::tempdir().unwrap();
            let engine = persistent(provider, &directory.path().join("deadlines.db"));
            engine.sql("SET idle_session_timeout = '1h'; SET idle_in_transaction_session_timeout = '1h'; SET transaction_timeout = '2h'", &[]).unwrap();
            if transaction {
                engine.sql("BEGIN; SELECT 1", &[]).unwrap();
            }
            assert_released(engine);
        }
    }
}

#[test]
fn dropping_a_parent_preserves_only_the_independent_sessions_resources() {
    for provider in 0..4 {
        let directory = tempfile::tempdir().unwrap();
        let engine = persistent(provider, &directory.path().join("sessions.db"));
        engine
            .sql("CREATE TABLE t(id integer); INSERT INTO t VALUES (1)", &[])
            .unwrap();
        let sibling = engine.new_session().unwrap();
        let parent = Arc::downgrade(&engine.session);
        drop(engine);
        assert!(parent.upgrade().is_none());
        assert_eq!(
            sibling.sql("SELECT id FROM t", &[]).unwrap().rows[0]["id"],
            Value::Int(1)
        );
        assert_released(sibling);
    }
}