Files
lancedb/nodejs/src/query.rs
T
Heng Ge f655f62e09 feat(query): add use_lsm to read MemWAL LSM data (#3489)
## What

MemWAL LSM **read** support. When a table has an LSM write spec
(`set_lsm_write_spec`), `merge_insert` upserts live in the MemWAL
active/frozen memtables and flushed SSTables until an external
compaction merges them into the base table, so a normal scan returns
**stale** data. This routes reads through Lance's `LsmScanner` so
queries also surface that in-flight data, deduplicated by primary key
(newest generation wins).

## How

- Adds a **`use_lsm: Option<bool>`** query flag, symmetric with the
`merge_insert` flag:
- **unset** — auto-route through the LSM scanner when the table carries
a write spec
- **`use_lsm(true)`** — force the LSM path; error if there is no spec
    - **`use_lsm(false)`** — read the base table only (the escape hatch)
- Plain scan, single-column full-text search, and single-vector ANN all
run through one `LsmScanner` (assembled from on-disk shard manifests
plus the cached writer's in-memory memtables), so a `where` predicate is
honored as a **prefilter** uniformly — including for vector search.
- **Compaction-aware snapshots:** an SSTable generation is dropped only
once it is both compacted into the base table and covered by the arm's
base-index catch-up (`index_catchup`); plain scans use the compaction
watermark alone.
- Query shapes the scanner cannot honor hard-error with guidance to set
`use_lsm(false)`: hybrid, multi/binary vectors, `with_row_id`,
reranking, `order_by`, dynamic/Substrait projection or filters,
`distance_range`, `use_index(false)`, postfilter, take-by-row-id/offset,
reads from a time-traveled version, and an unmaintained or ambiguous
(multiple) FTS/vector index. Namespace-pushdown queries fall back to
local execution when a spec is present; WAL-only writers are handled.
- Exposed across the Rust core and the Python (`use_lsm`) and TypeScript
(`useLsm`) bindings, including `TakeQuery`.

Rebased from Lance `7.2.0-beta.3` to `10.0.0-beta.3`.
2026-07-25 23:45:27 -07:00

706 lines
22 KiB
Rust

// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright The LanceDB Authors
use std::sync::Arc;
use crate::error::NapiErrorExt;
use crate::error::convert_error;
use crate::iterator::RecordBatchIterator;
use crate::rerankers::RerankHybridCallbackArgs;
use crate::rerankers::Reranker;
use crate::util::{parse_distance_type, schema_to_buffer};
use arrow_array::{
Array, Float16Array as ArrowFloat16Array, Float32Array as ArrowFloat32Array,
Float64Array as ArrowFloat64Array, UInt8Array as ArrowUInt8Array,
};
use arrow_buffer::ScalarBuffer;
use half::f16;
use lancedb::index::scalar::{
BooleanQuery, BoostQuery, FtsQuery, FullTextSearchQuery, MatchQuery, MultiMatchQuery, Occur,
Operator, PhraseQuery,
};
use lancedb::query::AnalyzePlanDistributedMetrics;
use lancedb::query::ExecutableQuery;
use lancedb::query::Query as LanceDbQuery;
use lancedb::query::QueryBase;
use lancedb::query::QueryExecutionOptions;
use lancedb::query::Select;
use lancedb::query::TakeQuery as LanceDbTakeQuery;
use lancedb::query::{ColumnOrdering as LanceDbColumnOrdering, VectorQuery as LanceDbVectorQuery};
use napi::bindgen_prelude::*;
use napi_derive::napi;
#[napi(object)]
pub struct ColumnOrdering {
pub ascending: bool,
pub nulls_first: bool,
pub column_name: String,
}
impl From<ColumnOrdering> for LanceDbColumnOrdering {
fn from(value: ColumnOrdering) -> Self {
match (value.ascending, value.nulls_first) {
(true, true) => Self::asc_nulls_first(value.column_name),
(true, false) => Self::asc_nulls_last(value.column_name),
(false, true) => Self::desc_nulls_first(value.column_name),
(false, false) => Self::desc_nulls_last(value.column_name),
}
}
}
fn analyze_plan_options(
distributed_metrics: Option<String>,
) -> napi::Result<QueryExecutionOptions> {
let analyze_plan_distributed_metrics =
match distributed_metrics.as_deref().unwrap_or("aggregate") {
"aggregate" => AnalyzePlanDistributedMetrics::Aggregate,
"per_worker" => AnalyzePlanDistributedMetrics::PerWorker,
"full" => AnalyzePlanDistributedMetrics::Full,
mode => {
return Err(napi::Error::from_reason(format!(
"Invalid distributedMetrics value '{}'. Expected one of: \
'aggregate', 'per_worker', 'full'",
mode
)));
}
};
let mut options = QueryExecutionOptions::default();
options.analyze_plan_distributed_metrics = analyze_plan_distributed_metrics;
Ok(options)
}
fn bytes_to_arrow_array(data: Uint8Array, dtype: String) -> napi::Result<Arc<dyn Array>> {
let buf = arrow_buffer::Buffer::from(data.to_vec());
let num_bytes = buf.len();
match dtype.as_str() {
"float16" => {
let scalar_buf = ScalarBuffer::<f16>::new(buf, 0, num_bytes / 2);
Ok(Arc::new(ArrowFloat16Array::new(scalar_buf, None)))
}
"float32" => {
let scalar_buf = ScalarBuffer::<f32>::new(buf, 0, num_bytes / 4);
Ok(Arc::new(ArrowFloat32Array::new(scalar_buf, None)))
}
"float64" => {
let scalar_buf = ScalarBuffer::<f64>::new(buf, 0, num_bytes / 8);
Ok(Arc::new(ArrowFloat64Array::new(scalar_buf, None)))
}
"uint8" => {
let scalar_buf = ScalarBuffer::<u8>::new(buf, 0, num_bytes);
Ok(Arc::new(ArrowUInt8Array::new(scalar_buf, None)))
}
_ => Err(napi::Error::from_reason(format!(
"Unsupported vector dtype: {}. Expected one of: float16, float32, float64, uint8",
dtype
))),
}
}
#[napi]
pub struct Query {
inner: LanceDbQuery,
}
#[napi]
impl Query {
pub fn new(query: LanceDbQuery) -> Self {
Self { inner: query }
}
// We cannot call this r#where because NAPI gets confused by the r#
#[napi]
pub fn only_if(&mut self, predicate: String) {
self.inner = self.inner.clone().only_if(predicate);
}
#[napi]
pub fn full_text_search(&mut self, query: Object) -> napi::Result<()> {
let query = parse_fts_query(query)?;
self.inner = self.inner.clone().full_text_search(query);
Ok(())
}
#[napi]
pub fn select(&mut self, columns: Vec<(String, String)>) {
self.inner = self.inner.clone().select(Select::dynamic(&columns));
}
#[napi]
pub fn select_columns(&mut self, columns: Vec<String>) {
self.inner = self.inner.clone().select(Select::columns(&columns));
}
#[napi]
pub fn limit(&mut self, limit: u32) {
self.inner = self.inner.clone().limit(limit as usize);
}
#[napi]
pub fn offset(&mut self, offset: u32) {
self.inner = self.inner.clone().offset(offset as usize);
}
#[napi]
pub fn nearest_to(&mut self, vector: Float32Array) -> Result<VectorQuery> {
let inner = self
.inner
.clone()
.nearest_to(vector.as_ref())
.default_error()?;
Ok(VectorQuery { inner })
}
#[napi]
pub fn nearest_to_raw(&mut self, data: Uint8Array, dtype: String) -> Result<VectorQuery> {
let array = bytes_to_arrow_array(data, dtype)?;
let inner = self.inner.clone().nearest_to(array).default_error()?;
Ok(VectorQuery { inner })
}
#[napi]
pub fn fast_search(&mut self) {
self.inner = self.inner.clone().fast_search();
}
#[napi]
pub fn with_row_id(&mut self) {
self.inner = self.inner.clone().with_row_id();
}
#[napi]
pub fn use_lsm(&mut self, enable: bool) {
self.inner = self.inner.clone().use_lsm(enable);
}
#[napi]
pub fn order_by(&mut self, ordering: Option<Vec<ColumnOrdering>>) -> napi::Result<()> {
let ordering = ordering.map(|ordering| {
ordering
.into_iter()
.map(LanceDbColumnOrdering::from)
.collect()
});
self.inner = self.inner.clone().order_by(ordering);
Ok(())
}
#[napi(catch_unwind)]
pub async fn output_schema(&self) -> napi::Result<Buffer> {
let schema = self.inner.output_schema().await.default_error()?;
schema_to_buffer(&schema)
}
#[napi(catch_unwind)]
pub async fn execute(
&self,
max_batch_length: Option<u32>,
timeout_ms: Option<u32>,
) -> napi::Result<RecordBatchIterator> {
let mut execution_opts = QueryExecutionOptions::default();
if let Some(max_batch_length) = max_batch_length {
execution_opts.max_batch_length = max_batch_length;
}
if let Some(timeout_ms) = timeout_ms {
execution_opts.timeout = Some(std::time::Duration::from_millis(timeout_ms as u64))
}
let inner_stream = self
.inner
.execute_with_options(execution_opts)
.await
.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to execute query stream: {}",
convert_error(&e)
))
})?;
Ok(RecordBatchIterator::new(inner_stream))
}
#[napi]
pub async fn explain_plan(&self, verbose: bool) -> napi::Result<String> {
self.inner.explain_plan(verbose).await.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to retrieve the query plan: {}",
convert_error(&e)
))
})
}
#[napi(catch_unwind)]
pub async fn analyze_plan(&self, distributed_metrics: Option<String>) -> napi::Result<String> {
let options = analyze_plan_options(distributed_metrics)?;
self.inner
.analyze_plan_with_options(options)
.await
.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to execute analyze plan: {}",
convert_error(&e)
))
})
}
}
#[napi]
pub struct VectorQuery {
inner: LanceDbVectorQuery,
}
#[napi]
impl VectorQuery {
#[napi]
pub fn column(&mut self, column: String) {
self.inner = self.inner.clone().column(&column);
}
#[napi]
pub fn add_query_vector(&mut self, vector: Float32Array) -> Result<()> {
self.inner = self
.inner
.clone()
.add_query_vector(vector.as_ref())
.default_error()?;
Ok(())
}
#[napi]
pub fn add_query_vector_raw(&mut self, data: Uint8Array, dtype: String) -> Result<()> {
let array = bytes_to_arrow_array(data, dtype)?;
self.inner = self.inner.clone().add_query_vector(array).default_error()?;
Ok(())
}
#[napi]
pub fn distance_type(&mut self, distance_type: String) -> napi::Result<()> {
let distance_type = parse_distance_type(distance_type)?;
self.inner = self.inner.clone().distance_type(distance_type);
Ok(())
}
#[napi]
pub fn postfilter(&mut self) {
self.inner = self.inner.clone().postfilter();
}
#[napi]
pub fn refine_factor(&mut self, refine_factor: u32) {
self.inner = self.inner.clone().refine_factor(refine_factor);
}
#[napi]
pub fn nprobes(&mut self, nprobe: u32) {
self.inner = self.inner.clone().nprobes(nprobe as usize);
}
#[napi]
pub fn minimum_nprobes(&mut self, minimum_nprobe: u32) -> napi::Result<()> {
self.inner = self
.inner
.clone()
.minimum_nprobes(minimum_nprobe as usize)
.default_error()?;
Ok(())
}
#[napi]
pub fn maximum_nprobes(&mut self, maximum_nprobes: u32) -> napi::Result<()> {
let maximum_nprobes = if maximum_nprobes == 0 {
None
} else {
Some(maximum_nprobes as usize)
};
self.inner = self
.inner
.clone()
.maximum_nprobes(maximum_nprobes)
.default_error()?;
Ok(())
}
#[napi]
pub fn distance_range(&mut self, lower_bound: Option<f64>, upper_bound: Option<f64>) {
// napi doesn't support f32, so we have to convert to f32
self.inner = self
.inner
.clone()
.distance_range(lower_bound.map(|v| v as f32), upper_bound.map(|v| v as f32));
}
#[napi]
pub fn ef(&mut self, ef: u32) {
self.inner = self.inner.clone().ef(ef as usize);
}
#[napi]
pub fn bypass_vector_index(&mut self) {
self.inner = self.inner.clone().bypass_vector_index()
}
#[napi]
pub fn only_if(&mut self, predicate: String) {
self.inner = self.inner.clone().only_if(predicate);
}
#[napi]
pub fn full_text_search(&mut self, query: Object) -> napi::Result<()> {
let query = parse_fts_query(query)?;
self.inner = self.inner.clone().full_text_search(query);
Ok(())
}
#[napi]
pub fn select(&mut self, columns: Vec<(String, String)>) {
self.inner = self.inner.clone().select(Select::dynamic(&columns));
}
#[napi]
pub fn select_columns(&mut self, columns: Vec<String>) {
self.inner = self.inner.clone().select(Select::columns(&columns));
}
#[napi]
pub fn limit(&mut self, limit: u32) {
self.inner = self.inner.clone().limit(limit as usize);
}
#[napi]
pub fn offset(&mut self, offset: u32) {
self.inner = self.inner.clone().offset(offset as usize);
}
#[napi]
pub fn fast_search(&mut self) {
self.inner = self.inner.clone().fast_search();
}
#[napi]
pub fn with_row_id(&mut self) {
self.inner = self.inner.clone().with_row_id();
}
#[napi]
pub fn use_lsm(&mut self, enable: bool) {
self.inner = self.inner.clone().use_lsm(enable);
}
#[napi]
pub fn rerank(
&mut self,
rerank_hybrid: Function<RerankHybridCallbackArgs, Promise<Buffer>>,
) -> napi::Result<()> {
let reranker = Reranker::new(rerank_hybrid)?;
self.inner = self.inner.clone().rerank(Arc::new(reranker));
Ok(())
}
#[napi]
pub fn order_by(&mut self, ordering: Option<Vec<ColumnOrdering>>) -> napi::Result<()> {
let ordering = ordering.map(|ordering| {
ordering
.into_iter()
.map(LanceDbColumnOrdering::from)
.collect()
});
self.inner = self.inner.clone().order_by(ordering);
Ok(())
}
#[napi(catch_unwind)]
pub async fn output_schema(&self) -> napi::Result<Buffer> {
let schema = self.inner.output_schema().await.default_error()?;
schema_to_buffer(&schema)
}
#[napi(catch_unwind)]
pub async fn execute(
&self,
max_batch_length: Option<u32>,
timeout_ms: Option<u32>,
) -> napi::Result<RecordBatchIterator> {
let mut execution_opts = QueryExecutionOptions::default();
if let Some(max_batch_length) = max_batch_length {
execution_opts.max_batch_length = max_batch_length;
}
if let Some(timeout_ms) = timeout_ms {
execution_opts.timeout = Some(std::time::Duration::from_millis(timeout_ms as u64))
}
let inner_stream = self
.inner
.execute_with_options(execution_opts)
.await
.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to execute query stream: {}",
convert_error(&e)
))
})?;
Ok(RecordBatchIterator::new(inner_stream))
}
#[napi]
pub async fn explain_plan(&self, verbose: bool) -> napi::Result<String> {
self.inner.explain_plan(verbose).await.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to retrieve the query plan: {}",
convert_error(&e)
))
})
}
#[napi(catch_unwind)]
pub async fn analyze_plan(&self, distributed_metrics: Option<String>) -> napi::Result<String> {
let options = analyze_plan_options(distributed_metrics)?;
self.inner
.analyze_plan_with_options(options)
.await
.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to execute analyze plan: {}",
convert_error(&e)
))
})
}
}
#[napi]
pub struct TakeQuery {
inner: LanceDbTakeQuery,
}
#[napi]
impl TakeQuery {
pub fn new(query: LanceDbTakeQuery) -> Self {
Self { inner: query }
}
#[napi]
pub fn select(&mut self, columns: Vec<(String, String)>) {
self.inner = self.inner.clone().select(Select::dynamic(&columns));
}
#[napi]
pub fn select_columns(&mut self, columns: Vec<String>) {
self.inner = self.inner.clone().select(Select::columns(&columns));
}
#[napi]
pub fn with_row_id(&mut self) {
self.inner = self.inner.clone().with_row_id();
}
#[napi]
pub fn use_lsm(&mut self, enable: bool) {
self.inner = self.inner.clone().use_lsm(enable);
}
#[napi(catch_unwind)]
pub async fn output_schema(&self) -> napi::Result<Buffer> {
let schema = self.inner.output_schema().await.default_error()?;
schema_to_buffer(&schema)
}
#[napi(catch_unwind)]
pub async fn execute(
&self,
max_batch_length: Option<u32>,
timeout_ms: Option<u32>,
) -> napi::Result<RecordBatchIterator> {
let mut execution_opts = QueryExecutionOptions::default();
if let Some(max_batch_length) = max_batch_length {
execution_opts.max_batch_length = max_batch_length;
}
if let Some(timeout_ms) = timeout_ms {
execution_opts.timeout = Some(std::time::Duration::from_millis(timeout_ms as u64))
}
let inner_stream = self
.inner
.execute_with_options(execution_opts)
.await
.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to execute query stream: {}",
convert_error(&e)
))
})?;
Ok(RecordBatchIterator::new(inner_stream))
}
#[napi]
pub async fn explain_plan(&self, verbose: bool) -> napi::Result<String> {
self.inner.explain_plan(verbose).await.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to retrieve the query plan: {}",
convert_error(&e)
))
})
}
#[napi(catch_unwind)]
pub async fn analyze_plan(&self, distributed_metrics: Option<String>) -> napi::Result<String> {
let options = analyze_plan_options(distributed_metrics)?;
self.inner
.analyze_plan_with_options(options)
.await
.map_err(|e| {
napi::Error::from_reason(format!(
"Failed to execute analyze plan: {}",
convert_error(&e)
))
})
}
}
#[napi]
#[derive(Debug, Clone)]
pub struct JsFullTextQuery {
pub(crate) inner: FtsQuery,
}
#[napi]
impl JsFullTextQuery {
#[napi(factory)]
pub fn match_query(
query: String,
column: String,
boost: f64,
fuzziness: Option<u32>,
max_expansions: u32,
operator: String,
prefix_length: u32,
) -> napi::Result<Self> {
Ok(Self {
inner: MatchQuery::new(query)
.with_column(Some(column))
.with_boost(boost as f32)
.with_fuzziness(fuzziness)
.with_max_expansions(max_expansions as usize)
.with_operator(
Operator::try_from(operator.as_str()).map_err(|e| {
napi::Error::from_reason(format!("Invalid operator: {}", e))
})?,
)
.with_prefix_length(prefix_length)
.into(),
})
}
#[napi(factory)]
pub fn phrase_query(query: String, column: String, slop: u32) -> napi::Result<Self> {
Ok(Self {
inner: PhraseQuery::new(query)
.with_column(Some(column))
.with_slop(slop)
.into(),
})
}
#[napi(factory)]
#[allow(clippy::use_self)] // NAPI doesn't allow Self here but clippy reports it
pub fn boost_query(
positive: &JsFullTextQuery,
negative: &JsFullTextQuery,
negative_boost: Option<f64>,
) -> napi::Result<Self> {
Ok(Self {
inner: BoostQuery::new(
positive.inner.clone(),
negative.inner.clone(),
negative_boost.map(|v| v as f32),
)
.into(),
})
}
#[napi(factory)]
pub fn multi_match_query(
query: String,
columns: Vec<String>,
boosts: Option<Vec<f64>>,
operator: String,
) -> napi::Result<Self> {
let q = match boosts {
Some(boosts) => MultiMatchQuery::try_new(query, columns)
.and_then(|q| q.try_with_boosts(boosts.into_iter().map(|v| v as f32).collect())),
None => MultiMatchQuery::try_new(query, columns),
}
.map_err(|e| {
napi::Error::from_reason(format!("Failed to create multi match query: {}", e))
})?;
let operator = Operator::try_from(operator.as_str()).map_err(|e| {
napi::Error::from_reason(format!("Invalid operator for multi match query: {}", e))
})?;
Ok(Self {
inner: q.with_operator(operator).into(),
})
}
#[napi(factory)]
#[allow(clippy::use_self)] // NAPI doesn't allow Self here but clippy reports it
pub fn boolean_query(queries: Vec<(String, &JsFullTextQuery)>) -> napi::Result<Self> {
let mut sub_queries = Vec::with_capacity(queries.len());
for (occur, q) in queries {
let occur = Occur::try_from(occur.as_str())
.map_err(|e| napi::Error::from_reason(e.to_string()))?;
sub_queries.push((occur, q.inner.clone()));
}
Ok(Self {
inner: BooleanQuery::new(sub_queries).into(),
})
}
#[napi(getter)]
pub fn query_type(&self) -> String {
match self.inner {
FtsQuery::Match(_) => "match".to_string(),
FtsQuery::Phrase(_) => "phrase".to_string(),
FtsQuery::Boost(_) => "boost".to_string(),
FtsQuery::MultiMatch(_) => "multi_match".to_string(),
FtsQuery::Boolean(_) => "boolean".to_string(),
}
}
}
fn parse_fts_query(query: Object) -> napi::Result<FullTextSearchQuery> {
if let Ok(Some(query)) = query.get::<&JsFullTextQuery>("query") {
Ok(FullTextSearchQuery::new_query(query.inner.clone()))
} else if let Ok(Some(query_text)) = query.get::<String>("query") {
let mut query_text = query_text;
let columns = query.get::<Option<Vec<String>>>("columns")?.flatten();
let is_phrase =
query_text.len() >= 2 && query_text.starts_with('"') && query_text.ends_with('"');
let is_multi_match = columns.as_ref().map(|cols| cols.len() > 1).unwrap_or(false);
if is_phrase {
// Remove the surrounding quotes for phrase queries
query_text = query_text[1..query_text.len() - 1].to_string();
}
let query: FtsQuery = match (is_phrase, is_multi_match) {
(false, _) => MatchQuery::new(query_text).into(),
(true, false) => PhraseQuery::new(query_text).into(),
(true, true) => {
return Err(napi::Error::from_reason(
"Phrase queries cannot be used with multiple columns.",
));
}
};
let mut query = FullTextSearchQuery::new_query(query);
if let Some(cols) = columns
&& !cols.is_empty()
{
query = query.with_columns(&cols).map_err(|e| {
napi::Error::from_reason(format!("Failed to set full text search columns: {}", e))
})?;
}
Ok(query)
} else {
Err(napi::Error::from_reason(
"Invalid full text search query object".to_string(),
))
}
}