vortex_file/
file.rs

1// SPDX-License-Identifier: Apache-2.0
2// SPDX-FileCopyrightText: Copyright the Vortex contributors
3
4//! This module defines the [`VortexFile`] struct, which represents a Vortex file on disk or in memory.
5//!
6//! The `VortexFile` provides methods for accessing file metadata, creating segment sources for reading
7//! data from the file, and initiating scans to read the file's contents into memory as Vortex arrays.
8
9use std::ops::Range;
10use std::sync::Arc;
11
12use itertools::Itertools;
13use vortex_array::ArrayRef;
14use vortex_array::Columnar;
15use vortex_array::IntoArray;
16use vortex_array::VortexSessionExecute;
17use vortex_array::arrays::ConstantArray;
18use vortex_array::dtype::DType;
19use vortex_array::dtype::Field;
20use vortex_array::dtype::FieldMask;
21use vortex_array::dtype::FieldPath;
22use vortex_array::dtype::FieldPathSet;
23use vortex_array::expr::Expression;
24use vortex_array::expr::pruning::checked_pruning_expr;
25use vortex_array::scalar_fn::internal::row_count::substitute_row_count;
26use vortex_error::VortexResult;
27use vortex_layout::LayoutReader;
28use vortex_layout::scan::layout::LayoutReaderDataSource;
29use vortex_layout::scan::scan_builder::ScanBuilder;
30use vortex_layout::scan::split_by::SplitBy;
31use vortex_layout::segments::SegmentSource;
32use vortex_scan::DataSourceRef;
33use vortex_session::VortexSession;
34use vortex_utils::aliases::hash_map::HashMap;
35
36use crate::FileStatistics;
37use crate::footer::Footer;
38use crate::pruning::extract_relevant_file_stats_as_struct_row;
39use crate::v2::FileStatsLayoutReader;
40
41/// Represents a Vortex file, providing access to its metadata and content.
42///
43/// A `VortexFile` is created by opening a Vortex file using [`VortexOpenOptions`](crate::VortexOpenOptions).
44/// It provides methods for accessing file metadata (such as row count, data type, and statistics)
45/// and for initiating scans to read the file's contents.
46#[derive(Clone)]
47pub struct VortexFile {
48    /// The footer of the Vortex file, containing metadata and layout information.
49    pub(crate) footer: Footer,
50    /// The segment source used to read segments from this file.
51    pub(crate) segment_source: Arc<dyn SegmentSource>,
52    /// The Vortex session used to open this file
53    pub(crate) session: VortexSession,
54}
55
56impl VortexFile {
57    /// Returns a reference to the file's footer, which contains metadata and layout information.
58    pub fn footer(&self) -> &Footer {
59        &self.footer
60    }
61
62    /// Returns the number of rows in the file.
63    pub fn row_count(&self) -> u64 {
64        self.footer.row_count()
65    }
66
67    /// Returns the data type of the file's contents.
68    pub fn dtype(&self) -> &DType {
69        self.footer.dtype()
70    }
71
72    /// Returns the file's statistics, if available.
73    ///
74    /// Statistics can be used for query optimization and data exploration.
75    pub fn file_stats(&self) -> Option<&FileStatistics> {
76        self.footer.statistics()
77    }
78
79    /// Create a new segment source for reading from the file.
80    ///
81    /// This may spawn a background I/O driver that will exit when the returned segment source
82    /// is dropped.
83    pub fn segment_source(&self) -> Arc<dyn SegmentSource> {
84        Arc::clone(&self.segment_source)
85    }
86
87    /// Create a new layout reader for the file.
88    pub fn layout_reader(&self) -> VortexResult<Arc<dyn LayoutReader>> {
89        let segment_source = self.segment_source();
90        self.footer
91            .layout()
92            // TODO(ngates): we may want to allow the user pass in a name here?
93            .new_reader("".into(), segment_source, &self.session)
94    }
95
96    /// Create a [`DataSource`](vortex_scan::DataSource) from this file for scanning.
97    ///
98    /// Wraps the file's layout reader with [`FileStatsLayoutReader`] (when file-level
99    /// statistics are available) and [`LayoutReaderDataSource`].
100    pub fn data_source(&self) -> VortexResult<DataSourceRef> {
101        let mut reader = self.layout_reader()?;
102        if let Some(stats) = self.file_stats().cloned() {
103            reader = Arc::new(FileStatsLayoutReader::new(
104                reader,
105                stats,
106                self.session.clone(),
107            ));
108        }
109        Ok(Arc::new(LayoutReaderDataSource::new(
110            reader,
111            self.session.clone(),
112        )))
113    }
114
115    /// Initiate a scan of the file, returning a builder for configuring the scan.
116    pub fn scan(&self) -> VortexResult<ScanBuilder<ArrayRef>> {
117        Ok(ScanBuilder::new(
118            self.session.clone(),
119            self.layout_reader()?,
120        ))
121    }
122
123    /// Returns `true` if file-level statistics prove the expression cannot
124    /// match any rows in this file.
125    ///
126    /// Row-count-aware pruning predicates are evaluated with the file's total
127    /// row count as their scope.
128    pub fn can_prune(&self, filter: &Expression) -> VortexResult<bool> {
129        let Some((stats, fields)) = self
130            .footer
131            .statistics()
132            .zip(self.footer.dtype().as_struct_fields_opt())
133        else {
134            return Ok(false);
135        };
136
137        let set = FieldPathSet::from_iter(
138            fields
139                .names()
140                .iter()
141                .zip(stats.stats_sets().iter())
142                .flat_map(|(name, stats)| {
143                    stats.iter().map(|(stat, _)| {
144                        FieldPath::from_iter([
145                            Field::Name(name.clone()),
146                            Field::Name(stat.name().into()),
147                        ])
148                    })
149                }),
150        );
151
152        let Some((predicate, required_stats)) = checked_pruning_expr(filter, &set) else {
153            return Ok(false);
154        };
155
156        let required_file_stats = HashMap::from_iter(
157            required_stats
158                .map()
159                .iter()
160                .map(|(path, stats)| (path.clone(), stats.clone())),
161        );
162
163        let Some(file_stats) = extract_relevant_file_stats_as_struct_row(
164            &required_file_stats,
165            stats.stats_sets(),
166            fields,
167        )?
168        else {
169            return Ok(false);
170        };
171
172        // Apply the predicate, then substitute any row_count placeholders in the resulting array
173        // tree with a ConstantArray carrying the file-level row count.
174        let applied = file_stats.apply(&predicate)?;
175        let row_count_replacement =
176            ConstantArray::new(self.footer.row_count(), applied.len()).into_array();
177        let applied = substitute_row_count(applied, &row_count_replacement)?;
178
179        let mut ctx = self.session.create_execution_ctx();
180        Ok(match applied.execute::<Columnar>(&mut ctx)? {
181            Columnar::Constant(s) => s.scalar().as_bool().value() == Some(true),
182            Columnar::Canonical(_) => false,
183        })
184    }
185
186    pub fn splits(&self) -> VortexResult<Vec<Range<u64>>> {
187        let reader = self.layout_reader()?;
188        Ok(SplitBy::Layout
189            .splits(reader.as_ref(), &(0..reader.row_count()), &[FieldMask::All])?
190            .into_iter()
191            .tuple_windows()
192            .map(|(start, end)| start..end)
193            .collect())
194    }
195}
vortex_file/file.rs

vortex_file/
file.rs
