uqa-engine 0.1.11

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
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172

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

//! Transaction data snapshots and rollback restoration.

use super::{Engine, EngineDataSnapshot, SQLError};
use crate::TableDataSnapshot;
use std::collections::BTreeMap;

impl Engine {
    pub(super) fn snapshot_transaction_data(&self) -> Result<Option<EngineDataSnapshot>, SQLError> {
        let mut tables = BTreeMap::new();
        for (name, table) in self.storage.tables.read().iter() {
            if self.storage.backend.is_some()
                && table.persistence != uqa_sql::ast::RelationPersistence::Temporary
            {
                continue;
            }
            // Capture an already-writable deep copy once. Calling `snapshot`
            // and then probing `writable_snapshot` would allocate and discard
            // a second database-sized clone before the statement even starts.
            let document_store: std::sync::Arc<dyn uqa_storage::DocumentStore> =
                std::sync::Arc::from(table.document_store.read().writable_snapshot().map_err(
                    |err| Self::storage_tx_error("snapshot writable document store", &err),
                )?);
            let inverted_index: std::sync::Arc<dyn uqa_storage::InvertedIndex> =
                std::sync::Arc::from(table.inverted_index.read().writable_snapshot().map_err(
                    |err| Self::storage_tx_error("snapshot writable inverted index", &err),
                )?);
            let mut vector_indexes = BTreeMap::new();
            for (field, index) in table.vector_indexes.read().iter() {
                let snapshot: std::sync::Arc<dyn uqa_storage::VectorIndex> =
                    std::sync::Arc::from(index.writable_snapshot().map_err(|err| {
                        Self::storage_tx_error("snapshot writable vector index", &err)
                    })?);
                vector_indexes.insert(field.clone(), snapshot);
            }
            tables.insert(
                name.clone(),
                TableDataSnapshot {
                    state: table.clone(),
                    storage_generation: table.storage_generation(),
                    document_store,
                    inverted_index,
                    vector_indexes,
                    fts_fields: table.fts_fields.read().clone(),
                    columns: table.columns.read().clone(),
                    next_id: *table.next_id.lock(),
                    analyzer: table.analyzer.read().clone(),
                    column_stats: table.column_stats.read().clone(),
                    column_stats_loaded: table
                        .column_stats_loaded
                        .load(std::sync::atomic::Ordering::Acquire),
                    column_stats_dirty: table
                        .column_stats_dirty
                        .load(std::sync::atomic::Ordering::Acquire),
                    table_checks: table.table_checks.read().clone(),
                    foreign_keys: table.foreign_keys.read().clone(),
                    key_constraints: table.key_constraints.read().clone(),
                    hierarchy: table.hierarchy.read().clone(),
                    doc_count_cache: table
                        .doc_count_cache
                        .load(std::sync::atomic::Ordering::Acquire),
                    doc_count_dirty: table
                        .doc_count_dirty
                        .load(std::sync::atomic::Ordering::Acquire),
                },
            );
        }
        Ok(Some(EngineDataSnapshot {
            tables,
            durable: self.durable.snapshot(),
            foreign_memory_tables: self.extensions.foreign_memory_tables.read().clone(),
        }))
    }

    /// Memory-engine rollback path: snapshots only exist when no persistent
    /// backend is attached, except for session-local temporary tables. These
    /// store operations remain fallible so a restore failure cannot leave a
    /// half-restored engine behind a successful-looking rollback.
    pub(super) fn restore_transaction_data(
        &self,
        snapshot: &EngineDataSnapshot,
    ) -> Result<(), SQLError> {
        self.clear_bayesian_params_cache();
        {
            let mut tables = self.storage.tables.write();
            tables.retain(|name, table| {
                snapshot.tables.contains_key(name)
                    || (self.storage.backend.is_some()
                        && table.persistence != uqa_sql::ast::RelationPersistence::Temporary)
            });
            for (name, table_snapshot) in &snapshot.tables {
                tables
                    .entry(name.clone())
                    .or_insert_with(|| table_snapshot.state.clone());
            }
        }
        for table_snapshot in snapshot.tables.values() {
            let table = &table_snapshot.state;
            let document_store = table_snapshot
                .document_store
                .writable_snapshot()
                .map_err(|err| Self::storage_tx_error("ROLLBACK document restore", &err))?;
            let inverted_index = table_snapshot
                .inverted_index
                .writable_snapshot()
                .map_err(|err| Self::storage_tx_error("ROLLBACK FTS restore", &err))?;
            let mut vector_indexes = BTreeMap::new();
            for (field, index) in &table_snapshot.vector_indexes {
                vector_indexes.insert(
                    field.clone(),
                    index
                        .writable_snapshot()
                        .map_err(|err| Self::storage_tx_error("ROLLBACK vector restore", &err))?,
                );
            }
            *table.document_store.write() = document_store;
            *table.storage_generation.write() = table_snapshot.storage_generation;
            *table.inverted_index.write() = inverted_index;
            *table.vector_indexes.write() = vector_indexes;
            table
                .fts_fields
                .write()
                .clone_from(&table_snapshot.fts_fields);
            table.columns.write().clone_from(&table_snapshot.columns);
            *table.next_id.lock() = table_snapshot.next_id;
            *table.analyzer.write() = table_snapshot.analyzer.clone();
            *table.column_stats.write() = table_snapshot.column_stats.clone();
            table.column_stats_loaded.store(
                table_snapshot.column_stats_loaded,
                std::sync::atomic::Ordering::Release,
            );
            table.column_stats_dirty.store(
                table_snapshot.column_stats_dirty,
                std::sync::atomic::Ordering::Release,
            );
            table
                .table_checks
                .write()
                .clone_from(&table_snapshot.table_checks);
            table
                .foreign_keys
                .write()
                .clone_from(&table_snapshot.foreign_keys);
            table
                .key_constraints
                .write()
                .clone_from(&table_snapshot.key_constraints);
            table
                .hierarchy
                .write()
                .clone_from(&table_snapshot.hierarchy);
            Self::value_indexes_clear(table);
            table.doc_count_cache.store(
                table_snapshot.doc_count_cache,
                std::sync::atomic::Ordering::Release,
            );
            table.doc_count_dirty.store(
                table_snapshot.doc_count_dirty,
                std::sync::atomic::Ordering::Release,
            );
        }
        self.durable.restore(&snapshot.durable);
        self.clear_regtype_output_cache();
        *self.extensions.foreign_memory_tables.write() = snapshot.foreign_memory_tables.clone();
        Ok(())
    }
}