Struct IndexBuilder 

pub struct IndexBuilder { /* private fields */ }

Builder for the create_index operation

The methods on this builder are used to specify options common to all indices.

Examples

Creating a basic vector index:

use lancedb::{connect, index::{Index, vector::IvfPqIndexBuilder}};

let db = connect("data/sample-lancedb").execute().await?;
let table = db.open_table("my_table").execute().await?;

// Create a vector index with default settings
table
    .create_index(&["vector"], Index::IvfPq(IvfPqIndexBuilder::default()))
    .execute()
    .await?;

Creating an index with a custom name:

use lancedb::{connect, index::{Index, vector::IvfPqIndexBuilder}};

let db = connect("data/sample-lancedb").execute().await?;
let table = db.open_table("my_table").execute().await?;

// Create a vector index with a custom name
table
    .create_index(&["embeddings"], Index::IvfPq(IvfPqIndexBuilder::default()))
    .name("my_embeddings_index".to_string())
    .execute()
    .await?;

Creating an untrained index (for scalar indices only):

use lancedb::{connect, index::{Index, scalar::BTreeIndexBuilder}};

let db = connect("data/sample-lancedb").execute().await?;
let table = db.open_table("my_table").execute().await?;

// Create a BTree index without training (creates empty index)
table
    .create_index(&["category"], Index::BTree(BTreeIndexBuilder::default()))
    .train(false)
    .name("category_index".to_string())
    .execute()
    .await?;

Creating a scalar index with all options:

use lancedb::{connect, index::{Index, scalar::BitmapIndexBuilder}};

let db = connect("data/sample-lancedb").execute().await?;
let table = db.open_table("my_table").execute().await?;

// Create a bitmap index with full configuration
table
    .create_index(&["status"], Index::Bitmap(BitmapIndexBuilder::default()))
    .name("status_bitmap_index".to_string())
    .train(true)  // Train the index with existing data
    .replace(false)  // Don't replace if index already exists
    .execute()
    .await?;

Implementations

impl IndexBuilder

pub fn replace(self, v: bool) -> Self

Whether to replace the existing index, the default is true.

If this is false, and another index already exists on the same columns and the same name, then an error will be returned. This is true even if that index is out of date.

pub fn name(self, v: String) -> Self

The name of the index. If not set, a default name will be generated.

Examples

use lancedb::{connect, index::{Index, scalar::BTreeIndexBuilder}};

let db = connect("data/sample-lancedb").execute().await?;
let table = db.open_table("my_table").execute().await?;

// Create an index with a custom name
table
    .create_index(&["user_id"], Index::BTree(BTreeIndexBuilder::default()))
    .name("user_id_btree_index".to_string())
    .execute()
    .await?;

pub fn train(self, v: bool) -> Self

Whether to train the index, the default is true.

If this is false, the index will not be trained and just created empty.

This is not supported for vector indices yet.

Examples

Creating an empty index that will be populated later:

use lancedb::{connect, index::{Index, scalar::BitmapIndexBuilder}};

let db = connect("data/sample-lancedb").execute().await?;
let table = db.open_table("my_table").execute().await?;

// Create an empty bitmap index (not trained with existing data)
table
    .create_index(&["category"], Index::Bitmap(BitmapIndexBuilder::default()))
    .train(false)  // Create empty index
    .name("category_bitmap".to_string())
    .execute()
    .await?;

Creating a trained index (default behavior):

use lancedb::{connect, index::{Index, scalar::BTreeIndexBuilder}};

let db = connect("data/sample-lancedb").execute().await?;
let table = db.open_table("my_table").execute().await?;

// Create a trained BTree index (includes existing data)
table
    .create_index(&["timestamp"], Index::BTree(BTreeIndexBuilder::default()))
    .train(true)  // Train with existing data (this is the default)
    .execute()
    .await?;

pub fn wait_timeout(self, d: Duration) -> Self

Duration of time to wait for asynchronous indexing to complete. If not set, create_index() will not wait.

This is not supported for NativeTable since indexing is synchronous.

pub async fn execute(self) -> Result<()>