sql_splitter/analyzer/
mod.rs

1use crate::parser::{determine_buffer_size, Parser, SqlDialect, StatementType};
2use ahash::AHashMap;
3use std::fs::File;
4use std::io::Read;
5use std::path::PathBuf;
6
7#[derive(Debug, Clone)]
8pub struct TableStats {
9    pub table_name: String,
10    pub insert_count: u64,
11    pub create_count: u64,
12    pub total_bytes: u64,
13    pub statement_count: u64,
14}
15
16impl TableStats {
17    fn new(table_name: String) -> Self {
18        Self {
19            table_name,
20            insert_count: 0,
21            create_count: 0,
22            total_bytes: 0,
23            statement_count: 0,
24        }
25    }
26}
27
28pub struct Analyzer {
29    input_file: PathBuf,
30    dialect: SqlDialect,
31    stats: AHashMap<String, TableStats>,
32}
33
34impl Analyzer {
35    pub fn new(input_file: PathBuf) -> Self {
36        Self {
37            input_file,
38            dialect: SqlDialect::default(),
39            stats: AHashMap::new(),
40        }
41    }
42
43    pub fn with_dialect(mut self, dialect: SqlDialect) -> Self {
44        self.dialect = dialect;
45        self
46    }
47
48    pub fn analyze(mut self) -> anyhow::Result<Vec<TableStats>> {
49        let file = File::open(&self.input_file)?;
50        let file_size = file.metadata()?.len();
51        let buffer_size = determine_buffer_size(file_size);
52        let dialect = self.dialect;
53
54        let mut parser = Parser::with_dialect(file, buffer_size, dialect);
55
56        while let Some(stmt) = parser.read_statement()? {
57            let (stmt_type, table_name) = Parser::<&[u8]>::parse_statement_with_dialect(&stmt, dialect);
58
59            if stmt_type == StatementType::Unknown || table_name.is_empty() {
60                continue;
61            }
62
63            self.update_stats(&table_name, stmt_type, stmt.len() as u64);
64        }
65
66        Ok(self.get_sorted_stats())
67    }
68
69    pub fn analyze_with_progress<F: Fn(u64)>(
70        mut self,
71        progress_fn: F,
72    ) -> anyhow::Result<Vec<TableStats>> {
73        let file = File::open(&self.input_file)?;
74        let file_size = file.metadata()?.len();
75        let buffer_size = determine_buffer_size(file_size);
76        let dialect = self.dialect;
77
78        let reader = ProgressReader::new(file, progress_fn);
79        let mut parser = Parser::with_dialect(reader, buffer_size, dialect);
80
81        while let Some(stmt) = parser.read_statement()? {
82            let (stmt_type, table_name) = Parser::<&[u8]>::parse_statement_with_dialect(&stmt, dialect);
83
84            if stmt_type == StatementType::Unknown || table_name.is_empty() {
85                continue;
86            }
87
88            self.update_stats(&table_name, stmt_type, stmt.len() as u64);
89        }
90
91        Ok(self.get_sorted_stats())
92    }
93
94    fn update_stats(&mut self, table_name: &str, stmt_type: StatementType, bytes: u64) {
95        let stats = self
96            .stats
97            .entry(table_name.to_string())
98            .or_insert_with(|| TableStats::new(table_name.to_string()));
99
100        stats.statement_count += 1;
101        stats.total_bytes += bytes;
102
103        match stmt_type {
104            StatementType::CreateTable => stats.create_count += 1,
105            StatementType::Insert | StatementType::Copy => stats.insert_count += 1,
106            _ => {}
107        }
108    }
109
110    fn get_sorted_stats(&self) -> Vec<TableStats> {
111        let mut result: Vec<TableStats> = self.stats.values().cloned().collect();
112        result.sort_by(|a, b| b.insert_count.cmp(&a.insert_count));
113        result
114    }
115}
116
117struct ProgressReader<R: Read, F: Fn(u64)> {
118    reader: R,
119    callback: F,
120    bytes_read: u64,
121}
122
123impl<R: Read, F: Fn(u64)> ProgressReader<R, F> {
124    fn new(reader: R, callback: F) -> Self {
125        Self {
126            reader,
127            callback,
128            bytes_read: 0,
129        }
130    }
131}
132
133impl<R: Read, F: Fn(u64)> Read for ProgressReader<R, F> {
134    fn read(&mut self, buf: &mut [u8]) -> std::io::Result<usize> {
135        let n = self.reader.read(buf)?;
136        self.bytes_read += n as u64;
137        (self.callback)(self.bytes_read);
138        Ok(n)
139    }
140}
141
142#[cfg(test)]
143mod tests {
144    use super::*;
145    use tempfile::TempDir;
146
147    #[test]
148    fn test_analyzer_basic() {
149        let temp_dir = TempDir::new().unwrap();
150        let input_file = temp_dir.path().join("input.sql");
151
152        std::fs::write(
153            &input_file,
154            b"CREATE TABLE users (id INT);\nINSERT INTO users VALUES (1);\nINSERT INTO users VALUES (2);\nCREATE TABLE posts (id INT);\nINSERT INTO posts VALUES (1);",
155        )
156        .unwrap();
157
158        let analyzer = Analyzer::new(input_file);
159        let stats = analyzer.analyze().unwrap();
160
161        assert_eq!(stats.len(), 2);
162
163        let users_stats = stats.iter().find(|s| s.table_name == "users").unwrap();
164        assert_eq!(users_stats.insert_count, 2);
165        assert_eq!(users_stats.create_count, 1);
166        assert_eq!(users_stats.statement_count, 3);
167
168        let posts_stats = stats.iter().find(|s| s.table_name == "posts").unwrap();
169        assert_eq!(posts_stats.insert_count, 1);
170        assert_eq!(posts_stats.create_count, 1);
171        assert_eq!(posts_stats.statement_count, 2);
172    }
173
174    #[test]
175    fn test_analyzer_sorted_by_insert_count() {
176        let temp_dir = TempDir::new().unwrap();
177        let input_file = temp_dir.path().join("input.sql");
178
179        std::fs::write(
180            &input_file,
181            b"CREATE TABLE a (id INT);\nINSERT INTO a VALUES (1);\nCREATE TABLE b (id INT);\nINSERT INTO b VALUES (1);\nINSERT INTO b VALUES (2);\nINSERT INTO b VALUES (3);",
182        )
183        .unwrap();
184
185        let analyzer = Analyzer::new(input_file);
186        let stats = analyzer.analyze().unwrap();
187
188        assert_eq!(stats[0].table_name, "b");
189        assert_eq!(stats[0].insert_count, 3);
190        assert_eq!(stats[1].table_name, "a");
191        assert_eq!(stats[1].insert_count, 1);
192    }
193}