oxirs_arq/advanced_optimizer/
index_advisor.rs1use std::collections::{HashMap, HashSet};
7use std::time::{Duration, Instant};
8
9use crate::algebra::{TriplePattern, Variable};
10use crate::optimizer::IndexType;
11
12#[derive(Clone)]
14pub struct IndexAdvisor {
15 #[allow(dead_code)]
16 query_patterns: HashMap<String, QueryPattern>,
17 index_usage_stats: HashMap<IndexType, IndexUsageStats>,
18 recommended_indexes: Vec<IndexRecommendation>,
19}
20
21#[derive(Debug, Clone)]
23pub struct QueryPattern {
24 pub pattern_hash: u64,
25 pub triple_patterns: Vec<TriplePattern>,
26 pub join_variables: HashSet<Variable>,
27 pub filter_variables: HashSet<Variable>,
28 pub frequency: usize,
29 pub avg_execution_time: Duration,
30 pub avg_cardinality: usize,
31}
32
33#[derive(Debug, Clone, Default)]
35pub struct IndexUsageStats {
36 pub access_count: usize,
37 pub total_access_time: Duration,
38 pub avg_selectivity: f64,
39 pub memory_usage: usize,
40 pub last_updated: Option<Instant>,
41}
42
43#[derive(Debug, Clone)]
45pub struct IndexRecommendation {
46 pub index_type: IndexType,
47 pub priority: IndexPriority,
48 pub estimated_benefit: f64,
49 pub estimated_cost: f64,
50 pub supporting_patterns: Vec<String>,
51 pub confidence: f64,
52}
53
54#[derive(Debug, Clone, PartialEq, PartialOrd)]
56pub enum IndexPriority {
57 Critical = 4,
58 High = 3,
59 Medium = 2,
60 Low = 1,
61}
62
63impl IndexAdvisor {
64 pub fn new() -> Self {
66 Self {
67 query_patterns: HashMap::new(),
68 index_usage_stats: HashMap::new(),
69 recommended_indexes: Vec::new(),
70 }
71 }
72
73 pub fn analyze_query_pattern(&mut self, _patterns: &[TriplePattern]) -> anyhow::Result<()> {
75 Ok(())
77 }
78
79 pub fn get_recommendations(&self) -> &[IndexRecommendation] {
81 &self.recommended_indexes
82 }
83
84 pub fn update_index_usage(
86 &mut self,
87 index_type: IndexType,
88 access_time: Duration,
89 selectivity: f64,
90 ) {
91 let stats = self.index_usage_stats.entry(index_type).or_default();
92 stats.access_count += 1;
93 stats.total_access_time += access_time;
94 stats.avg_selectivity = (stats.avg_selectivity * (stats.access_count - 1) as f64
95 + selectivity)
96 / stats.access_count as f64;
97 stats.last_updated = Some(Instant::now());
98 }
99
100 pub fn recommendations_count(&self) -> usize {
102 self.recommended_indexes.len()
103 }
104}
105
106impl Default for IndexAdvisor {
107 fn default() -> Self {
108 Self::new()
109 }
110}