Files
lancedb/docs/web-tests/rs/quickstart.rs
T
Jack Ye ddb318567a docs: complete SQL reference, enrich Functions drafts, rename OSS to Embedded (#4732)
## Summary

- Complete the SQL reference: `ATTACH DATABASE`, the `CHANGES` clause,
and
`dedupe()`/`duplicate_pairs()` (verified against current sophon source;
these were recently renamed from
`vector_dedup`/`vector_duplicate_pairs`).
  Fix the blob-column default-projection claim and add the previously
  undocumented `blob_descriptor()`.
- Enrich the gated Functions draft (still `.mintignore`'d, pre-release):
  chained Functions over blob outputs, GPU-produced blobs, Secrets,
  multi-input/output binding, `code=[module]` packaging.
- Upgrade the materialized-view and computed-column auto-refresh drafts
with
  precise, verified catch-up semantics, and add the missing `ALTER
  MATERIALIZED VIEW` / `CREATE ... WITH(...)` sections (also gated — the
  automatic-refresh scheduler is still dev/staging-only).
- Thread one running example (video frames → GPU extract/caption → dedup
→
auto-refreshing materialized view) through Functions, materialized
views,
and the LeRobotDataset integration guide instead of a separate tutorial.
- Rename "LanceDB OSS"/"OSS" to "LanceDB Embedded"/"Embedded" throughout
  (52 files); activate the existing availability-comparison mechanism on
  `basics/offerings.mdx` for a full feature-by-feature comparison table.
2026-10-29 10:16:03 -07:00

362 lines
11 KiB
Rust

// SPDX-License-Identifier: Apache-2.0
// SPDX-FileCopyrightText: Copyright The LanceDB Authors
use lancedb::{connect, table::NewColumnTransform};
// --8<-- [start:quickstart_define_struct]
use std::sync::Arc;
use lancedb::arrow::arrow_array::types::Float32Type;
use lancedb::arrow::arrow_array::{
FixedSizeListArray, Int8Array, LargeStringArray, RecordBatch, RecordBatchIterator,
RecordBatchReader, StructArray,
};
use lancedb::arrow::arrow_schema::{DataType, Field, FieldRef, Fields, Schema};
// Define structs representing the data schema
#[derive(Debug, Clone)]
struct Stats {
motion: i8,
sharpness: i8,
exposure: i8,
framing: i8,
}
#[derive(Debug, Clone)]
struct Frame {
frame_id: String,
video_id: String,
caption: String,
stats: Stats,
embedding: [f32; 4],
}
fn frames_schema() -> Arc<Schema> {
Arc::new(Schema::new(vec![
Field::new("frame_id", DataType::LargeUtf8, false),
Field::new("video_id", DataType::LargeUtf8, false),
Field::new("caption", DataType::LargeUtf8, false),
Field::new(
"stats",
DataType::Struct(Fields::from(vec![
Arc::new(Field::new("motion", DataType::Int8, false)),
Arc::new(Field::new("sharpness", DataType::Int8, false)),
Arc::new(Field::new("exposure", DataType::Int8, false)),
Arc::new(Field::new("framing", DataType::Int8, false)),
])),
false,
),
Field::new(
"embedding",
DataType::FixedSizeList(Arc::new(Field::new("item", DataType::Float32, true)), 4),
false,
),
]))
}
fn frames_to_reader(
schema: Arc<Schema>,
rows: &[Frame],
) -> Box<dyn RecordBatchReader + Send> {
let frame_ids = LargeStringArray::from_iter_values(rows.iter().map(|row| row.frame_id.as_str()));
let video_ids = LargeStringArray::from_iter_values(rows.iter().map(|row| row.video_id.as_str()));
let captions =
LargeStringArray::from_iter_values(rows.iter().map(|row| row.caption.as_str()));
let motion = Int8Array::from_iter_values(rows.iter().map(|row| row.stats.motion));
let sharpness = Int8Array::from_iter_values(rows.iter().map(|row| row.stats.sharpness));
let exposure = Int8Array::from_iter_values(rows.iter().map(|row| row.stats.exposure));
let framing = Int8Array::from_iter_values(rows.iter().map(|row| row.stats.framing));
let stats_fields: Vec<FieldRef> = vec![
Arc::new(Field::new("motion", DataType::Int8, false)),
Arc::new(Field::new("sharpness", DataType::Int8, false)),
Arc::new(Field::new("exposure", DataType::Int8, false)),
Arc::new(Field::new("framing", DataType::Int8, false)),
];
let stats = StructArray::new(
stats_fields.into(),
vec![
Arc::new(motion),
Arc::new(sharpness),
Arc::new(exposure),
Arc::new(framing),
],
None,
);
let embeddings = FixedSizeListArray::from_iter_primitive::<Float32Type, _, _>(
rows.iter()
.map(|row| Some(row.embedding.iter().copied().map(Some).collect::<Vec<_>>())),
4,
);
let batch = RecordBatch::try_new(
schema.clone(),
vec![
Arc::new(frame_ids),
Arc::new(video_ids),
Arc::new(captions),
Arc::new(stats),
Arc::new(embeddings),
],
)
.unwrap();
Box::new(RecordBatchIterator::new(
vec![Ok(batch)].into_iter(),
schema,
))
}
// --8<-- [end:quickstart_define_struct]
#[tokio::main]
async fn main() {
let temp_dir = tempfile::tempdir().unwrap();
let uri = temp_dir.path().to_str().unwrap();
let db = connect(uri).execute().await.unwrap();
// --8<-- [start:quickstart_data]
let data = vec![
Frame {
frame_id: "1".to_string(),
video_id: "clip-1".to_string(),
caption: "a robot arm reaching toward a cup".to_string(),
stats: Stats {
motion: 3,
sharpness: 4,
exposure: 4,
framing: 3,
},
embedding: [0.7, 0.1, 0.9, 0.7],
},
Frame {
frame_id: "2".to_string(),
video_id: "clip-1".to_string(),
caption: "a two-finger gripper closing on a cup".to_string(),
stats: Stats {
motion: 5,
sharpness: 4,
exposure: 5,
framing: 2,
},
embedding: [0.2, 0.9, 0.4, 0.9],
},
Frame {
frame_id: "3".to_string(),
video_id: "clip-2".to_string(),
caption: "a robot arm holding a cup steady".to_string(),
stats: Stats {
motion: 2,
sharpness: 3,
exposure: 3,
framing: 4,
},
embedding: [0.9, 0.1, 0.5, 0.4],
},
];
// --8<-- [end:quickstart_data]
// --8<-- [start:quickstart_create_table]
use lancedb::database::CreateTableMode;
let schema = frames_schema();
let table = db
.create_table("frames", frames_to_reader(schema.clone(), &data))
.mode(CreateTableMode::Overwrite)
.execute()
.await
.unwrap();
// --8<-- [end:quickstart_create_table]
assert_eq!(table.count_rows(None).await.unwrap(), 3);
// --8<-- [start:quickstart_add_data]
let more_data = vec![Frame {
frame_id: "4".to_string(),
video_id: "clip-2".to_string(),
caption: "a gripper lowering a cup onto the table".to_string(),
stats: Stats {
motion: 5,
sharpness: 4,
exposure: 4,
framing: 2,
},
embedding: [0.3, 0.9, 0.6, 0.8],
}];
table
.add(frames_to_reader(schema.clone(), &more_data))
.execute()
.await
.unwrap();
// --8<-- [end:quickstart_add_data]
assert_eq!(table.count_rows(None).await.unwrap(), 4);
// --8<-- [start:quickstart_vector_search_1]
use lancedb::arrow::IntoPolars;
use lancedb::query::{ExecutableQuery, QueryBase, Select};
// Search for frames similar to "a gripper closing on an object"
let query_vector = [0.2, 0.8, 0.4, 0.9];
let result = table
.query()
.nearest_to(&query_vector)
.unwrap()
.select(Select::Columns(vec![
"frame_id".to_string(),
"video_id".to_string(),
"caption".to_string(),
"_distance".to_string(),
]))
.limit(2)
.execute()
.await
.unwrap()
.into_polars()
.await
.unwrap();
println!("{result:?}");
// --8<-- [end:quickstart_vector_search_1]
let frame_id_col = result.column("frame_id").unwrap().str().unwrap();
assert_eq!(frame_id_col.get(0).unwrap(), "2");
assert_eq!(frame_id_col.get(1).unwrap(), "4");
// --8<-- [start:quickstart_curate_with_metadata]
let curated = table
.query()
.nearest_to(&query_vector)
.unwrap()
.only_if("stats.motion >= 4")
.select(Select::Columns(vec![
"frame_id".to_string(),
"video_id".to_string(),
"caption".to_string(),
"_distance".to_string(),
]))
.limit(2)
.execute()
.await
.unwrap()
.into_polars()
.await
.unwrap();
println!("{curated:?}");
// --8<-- [end:quickstart_curate_with_metadata]
let curated_frame_id_col = curated.column("frame_id").unwrap().str().unwrap();
assert_eq!(curated_frame_id_col.get(0).unwrap(), "2");
assert_eq!(curated_frame_id_col.get(1).unwrap(), "4");
// --8<-- [start:quickstart_output_array]
let result = table
.query()
.nearest_to(&query_vector)
.unwrap()
.select(Select::Columns(vec![
"frame_id".to_string(),
"video_id".to_string(),
"caption".to_string(),
"_distance".to_string(),
]))
.limit(2)
.execute()
.await
.unwrap()
.into_polars()
.await
.unwrap();
println!("{result:?}");
// --8<-- [end:quickstart_output_array]
let frame_id_col = result.column("frame_id").unwrap().str().unwrap();
assert_eq!(frame_id_col.get(0).unwrap(), "2");
// --8<-- [start:quickstart_add_feature]
table
.add_columns(
NewColumnTransform::SqlExpressions(vec![(
"quality_score".to_string(),
"cast(((stats.motion + stats.sharpness + stats.exposure + stats.framing) / 4.0) as float)"
.to_string(),
)]),
None,
)
.await
.unwrap();
// --8<-- [end:quickstart_add_feature]
// --8<-- [start:quickstart_query_feature]
let features = table
.query()
.select(Select::Columns(vec![
"frame_id".to_string(),
"video_id".to_string(),
"quality_score".to_string(),
]))
.execute()
.await
.unwrap()
.into_polars()
.await
.unwrap();
println!("{features:?}");
// --8<-- [end:quickstart_query_feature]
assert_eq!(features.column("quality_score").unwrap().len(), 4);
// What the quickstart's download step leaves in an application's directory.
let app = tempfile::tempdir().unwrap();
std::fs::create_dir(app.path().join("data")).unwrap();
std::fs::copy(
std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
.join("../../web/static/assets/images/quickstart/sir-lancelot.jpg"),
app.path().join("data/sample-frame.jpg"),
)
.unwrap();
std::env::set_current_dir(app.path()).unwrap();
// --8<-- [start:quickstart_multimodal_bytes]
use lancedb::arrow::arrow_array::BinaryArray;
let image_bytes = std::fs::read("data/sample-frame.jpg").unwrap();
let image_schema = Arc::new(Schema::new(vec![
Field::new("frame_id", DataType::LargeUtf8, false),
Field::new("caption", DataType::LargeUtf8, false),
Field::new("image", DataType::Binary, false),
Field::new(
"embedding",
DataType::FixedSizeList(Arc::new(Field::new("item", DataType::Float32, true)), 4),
false,
),
]));
let image_embeddings = [[0.9_f32, 0.1, 0.5, 0.4]];
let image_batch = RecordBatch::try_new(
image_schema.clone(),
vec![
Arc::new(LargeStringArray::from_iter_values(["thumb-1"])),
Arc::new(LargeStringArray::from_iter_values([
"Sample frame thumbnail",
])),
Arc::new(BinaryArray::from_iter_values([image_bytes.as_slice()])),
Arc::new(
FixedSizeListArray::from_iter_primitive::<Float32Type, _, _>(
image_embeddings
.iter()
.map(|vector| Some(vector.iter().copied().map(Some).collect::<Vec<_>>())),
4,
),
),
],
)
.unwrap();
let image_reader: Box<dyn RecordBatchReader + Send> = Box::new(RecordBatchIterator::new(
vec![Ok(image_batch)].into_iter(),
image_schema,
));
let multimodal_table = db
.create_table("frame_images", image_reader)
.mode(CreateTableMode::Overwrite)
.execute()
.await
.unwrap();
// --8<-- [end:quickstart_multimodal_bytes]
assert_eq!(multimodal_table.count_rows(None).await.unwrap(), 1);
}