Find rows (TypeScript)

Finds rows in a table using filter and sort clauses, including vector search.

For general information about working with tables and rows, see About tables with the Data API (TypeScript).

Ready to write code? See the examples for this method to get started. If you are new to the Data API, check out the quickstart.

Result

Returns a cursor (TableFindCursor<Schema>) for iterating over rows that match the specified filter and sort clauses.

The columns included in the returned rows depend on the subset of columns that were requested in the projection.

If requested and applicable, each row will also include a $similarity key with a numeric similarity score that represents the closeness of the sort vector and the row’s vector.

You must iterate over the cursor to fetch matching rows. For details about iteration, see Iterate over found rows.

Parameters

Use the find method, which belongs to the Table class.

Method signature

find(
  filter: TableFilter<Schema>,
  options?: {
    sort?: Sort,
    projection?: Projection,
    limit?: number,
    skip?: number
    includeSimilarity?: boolean,
    initialPageState?: string,
    timeout?: number | TimeoutDescriptor,
  }
): TableFindCursor<Schema, Schema> | null

For best performance, filter and sort on indexed columns, partition keys, and clustering keys.

Filtering on non-indexed columns is inefficient and resource-intensive, especially for large datasets. With the Data API clients, such operations can hit the client timeout limit before the underlying HTTP operation is complete. If you filter on non-indexed columns, the Data API will give a warning.

An empty filter or omitted filter may also result in an inefficient and long-running operation.

Additionally, the Data API can perform in-memory sorting, depending on the columns you sort on, the table’s partitioning structure, and whether the sorted columns are indexed. In-memory sorts can have performance implications.

Name Type Summary

Name	Type	Summary
`filter`	`TableFilter`	Optional. An object that defines filter criteria using the Data API filter syntax. The method only finds rows that match the filter criteria. Filters can improve performance by reducing the number of rows that the Data API processes. For a list of available filter operators and more examples, see Filter operators for tables (TypeScript). To perform a vector search, use `sort` instead of `filter`. To avoid fetching unnecessary rows, which can contain tombstones, DataStax recommends that you use a filter that limits the number of rows scanned. For example, filter on partition key columns or indexed columns. Default: No filter For an example, see Use filters to find rows.
`options`	`TableFindOptions`	Optional. The options for this operation. See Properties of `options` for more details.

filter

TableFilter

Optional. An object that defines filter criteria using the Data API filter syntax. The method only finds rows that match the filter criteria. Filters can improve performance by reducing the number of rows that the Data API processes.

For a list of available filter operators and more examples, see Filter operators for tables (TypeScript).

To perform a vector search, use sort instead of filter.

To avoid fetching unnecessary rows, which can contain tombstones, DataStax recommends that you use a filter that limits the number of rows scanned. For example, filter on partition key columns or indexed columns.

Default: No filter

For an example, see Use filters to find rows.

options

TableFindOptions

Optional. The options for this operation. See Properties of options for more details.

Properties of `options`
Name	Type	Summary
`sort`	`Sort`	Optional. Sorts rows by one or more columns, or performs a vector search. For more information, see Sort clauses for tables (TypeScript). For examples, see Use sorting to find rows and Use vector search with a search vector to find rows.
`projection`	`Projection`	Optional. Controls which columns are included or excluded in the returned rows. For more information, see Projections for tables (TypeScript). DataStax recommends a projection to avoid unnecessarily returning large columns, such as `vector` columns with highly dimensional embeddings. Default: All columns For examples, see Include only specific columns in the response and Exclude specific columns from the response.
`skip`	`number`	Optional. The number of rows to bypass (skip) before returning rows. The API excludes the first `n` rows matching the query, and the results begin at the `n+1` row. This parameter only applies if you also explicitly specify an ascending or descending sort criterion. This parameter is not valid with vector search.
`limit`	`number`	Optional. Limit the total number of rows returned. Once `limit` is reached, or the cursor is exhausted due to lack of matching rows, nothing more is returned. For vector search, a lower limit reduces the accuracy of the search and the time required for the search.
`includeSimilarity`	`boolean`	Optional. Whether to include a `$similarity` property in the response. The `$similarity` value represents the closeness of the sort vector and the row’s vector. Default: false If you use a projection and you set the `includeSimilarity` parameter to `true` for a vector search, you must manually include `$similarity` in the type of the returned rows. For an example, see Include the similarity score with the result.
`initialPageState`	`string`	Optional. The `nextPageState` value from the response of `fetchNextPage()` called on a previous cursor. Used to manually request the next page of results. This is useful for cases where an external action triggers fetching the next page of results. For usage, see Iterate over found rows.
`timeout`	`number` \| `TimeoutDescriptor`	Optional. The timeout to apply to this method.

Examples

The following examples demonstrate how to find rows in a table.

Use filters to find rows

You can use a filter to find rows that match specific criteria. For example, you can find rows with an is_checked_out value of false and a number_of_pages value less than 300.

For optimal performance, you only filter on indexed columns. The Data API returns a warning if you filter on a non-indexed column.

For a list of available filter operators, see Filter operators for tables (TypeScript).

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find({
    $and: [{ is_checked_out: false }, { number_of_pages: { $lt: 300 } }],
  });

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Use vector search with a search vector to find rows

Perform a vector search by providing a search vector in the sort clause. This returns the row whose vector column value is most similar to the provided search vector.

The vector column must be indexed.

If your table has multiple vector columns, you can only sort on one vector column at a time.

You can use the DataAPIVector class to binary-encode your search vector. DataStax recommends that you always use a DataAPIVector object instead of a list of floats to improve performance.

When you read the value of a vector column, the client always returns a DataAPIVector object, unless you change the default serialization/deserialization behavior. You can use vector.asArray() to lazily convert a DataAPIVector object to an array.

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
  DataAPIVector,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    {},
    { sort: { summary_genres_vector: new DataAPIVector([0.08, -0.62, 0.39]) } },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Use lexicographical matching to find rows

Lexicographical matching is currently in public preview. Development is ongoing, and the features and functionality are subject to change. Hyper-Converged Database (HCD), and the use of such, is subject to the DataStax Preview Terms.

There are two ways to use lexicographical matching to find rows with the Data API:

Sort to find rows with a text or ascii column value that is most relevant to a given string of space-separated keywords or terms.
Filter with the $match operator to find rows with a text or ascii column value that is a lexicographical match to the specified string of space-separated keywords or terms

You can use these strategies together or separately.

Lexicographical matching is only available for text or ascii columns that have a text index, not a regular index. For more information, see Create a text index (TypeScript) and Indexes in tables (TypeScript).

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    { summary: { $match: "futuristic laboratory discovery" } },
    {
      sort: {
        summary: "futuristic laboratory",
      },
    },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Use sorting to find rows

You can use a sort clause to sort rows by one or more columns.

For best performance, only sort on columns that are indexed or that are part of the primary key.

For more information, see Sort clauses for tables (TypeScript).

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    { is_checked_out: false },
    {
      sort: {
        rating: 1, // ascending
        title: -1, // descending
      },
    },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Use an empty filter to find all rows

To find all rows, use an empty filter.

Avoid this if you have a large number of rows.

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find({});

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Include the similarity score with the result

If you use a vector search to find rows, you can also include a $similarity property in the result. The $similarity value represents the closeness of the sort vector and the value of the row’s vector column.

This parameter doesn’t work with vectorize; it only works if you provide the search vector for vector search directly.

The client always returns the similarity score as a DataAPIVector object, unless you change the default serialization/deserialization behavior. You can use vector.asArray() to lazily convert a DataAPIVector object to an array.

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
  DataAPIVector,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    {},
    {
      sort: { summary_genres_vector: new DataAPIVector([0.08, -0.62, 0.39]) },
      includeSimilarity: true,
    },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row.$similarity);
  }
})();

Include only specific columns in the response

To specify which columns to include or exclude in the returned row, use a projection.

The following example demonstrates an inclusive projection.

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    { number_of_pages: { $lt: 300 } },
    { projection: { is_checked_out: true, title: true } },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Exclude specific columns from the response

To specify which columns to include or exclude in the returned row, use a projection.

The following example demonstrates an exclusive projection.

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    { number_of_pages: { $lt: 300 } },
    { projection: { is_checked_out: false, title: false } },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Limit the number of rows returned

Specify a limit to only fetch up to a certain number of rows.

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    {
      $and: [{ is_checked_out: false }, { number_of_pages: { $lt: 300 } }],
    },
    { limit: 3 },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Skip rows

You can specify a number of rows to skip (bypass) before returning rows.

You can only do this if your find explicitly includes an ascending or descending sort criterion. You cannot do this in conjunction with vector search.

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    { is_checked_out: false },
    {
      sort: {
        rating: 1, // ascending
        title: -1, // descending
      },
      skip: 5,
    },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Use filter, sort, and projection together

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find(
    {
      $and: [{ is_checked_out: false }, { number_of_pages: { $lt: 300 } }],
    },
    {
      sort: {
        rating: 1, // ascending
        title: -1, // descending
      },
      projection: {
        is_checked_out: true,
        title: true,
      },
    },
  );

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Iterate over found rows

Use a for loop and the next() method on the cursor to iterate over the found rows. The client will periodically fetch more rows until no matching rows remain.

Alternatively, you can use the initialPageState parameter to fetch a specific page of results. This is useful for cases where an external action triggers fetching the next page of results. For example, you might use this feature if you implement a "Load More" button or an infinite scroll interface.

If you need a list of all results, call toArray(). However, the time and memory required for this operation depend on the number of results. This is not recommended when you expect a large number of roes.

Example using for and next():

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

(async function () {
  // Find rows
  const cursor = table.find({
    $and: [{ is_checked_out: false }, { number_of_pages: { $lt: 300 } }],
  });

  // Get the next item in the cursor
  console.log(await cursor.next());

  // Iterate over the found rows
  for await (const row of cursor) {
    console.log(row);
  }
})();

Example using initialPageState:

import {
  DataAPIClient,
  UsernamePasswordTokenProvider,
} from "@datastax/astra-db-ts";

// Get an existing table
const client = new DataAPIClient({ environment: "hcd" });
const database = client.db("API_ENDPOINT", {
  token: new UsernamePasswordTokenProvider("USERNAME", "PASSWORD"),
  keyspace: "KEYSPACE_NAME",
});
const table = database.table("TABLE_NAME");

// Create the filter
const filter = {
  $and: [{ is_checked_out: false }, { number_of_pages: { $lt: 300 } }],
};

(async function () {
  // Get the first page
  const cursor1 = table.find(filter);
  const page1 = await cursor1.fetchNextPage();
  const results1 = page1.result;
  for (const row of results1) {
    console.log(row);
  }
  const paginationState1 = page1.nextPageState;

  // Get the next page
  if (paginationState1) {
    const cursor2 = table.find(filter, { initialPageState: paginationState1 });
    const page2 = await cursor2.fetchNextPage();
    const results2 = page2.result;
    for (const row of results2) {
      console.log(row);
    }
    const paginationState2 = page2.nextPageState;
  }
})();

Client reference

For more information, see the client reference.

Find rows (TypeScript)

Result

Parameters

Examples

Use filters to find rows

Use vector search with a search vector to find rows

Use lexicographical matching to find rows

Use sorting to find rows

Use an empty filter to find all rows

Include the similarity score with the result

Include only specific columns in the response

Exclude specific columns from the response

Limit the number of rows returned

Skip rows

Use filter, sort, and projection together

Iterate over found rows

Client reference

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