Files
lancedb/docs/web/management/database.mdx
T
Brendan Clement 622e6078c1 docs: describe materialized-view refresh as a full rebuild
Main now rebuilds a materialized view completely on every refresh
(#4373): there is no incremental mode, no `full` argument and no
stable-row-ID requirement on the source. The example ran against the
SDK built from this branch (0.40.0b13) failed, because a refresh after
adding Bea writes both matching rows, not one.

The example now creates its source with the default options and expects
two rows written by the refresh, and its generated snippet is
regenerated. Separate tests cover `with_no_data` (one matching row on
the first refresh) and refreshing to an earlier source version. The
refresh page explains the full rebuild and keeps the #incremental and
#stable-row-ids anchors for the sections that replace them. Its version
note now says what the published 0.39.0 does differently, as observed
with that release.

The management, table, database, limits, architecture and data-types
pages no longer say a view's source needs stable row ids, and the
feature-engineering and tutorial summaries no longer call refreshes
incremental.
2026-10-06 20:44:06 -07:00

191 lines
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Plaintext

---
title: "Database"
sidebarTitle: "Database"
description: "Connecting to LanceDB: the URI forms, their options, and what each one changes."
icon: database
keywords: ["connect", "database", "uri", "api key", "storage options", "consistency"]
---
A database is the root of a [catalog](/basics/catalog). A connection opens
exactly one, and every other object is reached through it.
Connecting is the one decision that reaches furthest: the URI you pass decides
where queries execute, which features exist, and what a table handle actually
is.
## The three URI forms {#uris}
<CodeGroup>
```python Python icon="python"
import lancedb
db = lancedb.connect("./.lancedb") # local directory
db = lancedb.connect("s3://bucket/path") # object storage
db = lancedb.connect("db://my-database", api_key="...") # a deployment
```
```typescript TypeScript icon="square-js"
import * as lancedb from "@lancedb/lancedb";
const db = await lancedb.connect("./.lancedb");
const db = await lancedb.connect("s3://bucket/path");
const db = await lancedb.connect("db://my-database", { apiKey: "..." });
```
</CodeGroup>
The first two are **embedded**: your process opens Lance tables directly from
storage and does the work itself. The third talks to a **deployment**.
| | Embedded | Deployment |
| --- | --- | --- |
| Where queries run | in your process | on the server |
| Table handle | `LanceTable` | `RemoteTable` |
| [SQL](/basics/sql) | -- | yes |
| Server-side [jobs](/basics/jobs) | -- | yes |
| [Functions](/management/function) | -- | yes |
| [Authorization](/governance/authorization) | storage permissions | granted per object |
![](/static/assets/images/overview/understanding-tables.png)
Both handles expose the same table API -- create, open, mutate, query -- so
application code moves between them by changing the URI. What differs is where
resolution and execution happen, and therefore which operations exist at all.
## Connecting to a deployment {#deployment}
<Badge color="red">Enterprise</Badge>
<CodeGroup>
```python Python icon="python"
db = lancedb.connect(
"db://my-database",
api_key="...",
region="us-east-1",
)
```
```typescript TypeScript icon="square-js"
const db = await lancedb.connect("db://my-database", {
apiKey: "...",
region: "us-east-1",
});
```
</CodeGroup>
| Option | Meaning |
| --- | --- |
| `api_key` / `apiKey` | authenticates the connection -- see [Authentication](/enterprise/authentication) |
| `region` | which region hosts the database. Defaults to `us-east-1` |
| `host_override` / `hostOverride` | point at a specific endpoint instead of the regional one |
| `sql_host_override` | the same, for the [SQL endpoint](/sql#connecting). Python only |
| `client_config` / `clientConfig` | retries, timeouts, and connection pooling |
An API key belongs in the environment, not in source. `region` is easy to get
wrong silently -- the default is `us-east-1` whether or not that is where your
database lives, and a wrong region fails as a connection error rather than a
helpful one.
## Storage options {#storage-options}
`storage_options` configures the underlying object store -- credentials,
endpoints, and defaults for tables created through this connection:
<CodeGroup>
```python Python icon="python"
db = lancedb.connect(
"s3://bucket/path",
storage_options={"new_table_enable_stable_row_ids": "true"},
)
```
```typescript TypeScript icon="square-js"
const db = await lancedb.connect("s3://bucket/path", {
storageOptions: { new_table_enable_stable_row_ids: "true" },
});
```
</CodeGroup>
<Warning>
`new_table_enable_stable_row_ids` is worth setting deliberately: stable row ids
cannot be enabled after a table exists.
</Warning>
See [Storage](/deployment/storage) for the full set, including per-cloud credentials.
## Read consistency {#consistency}
`read_consistency_interval` controls how often a connection checks for versions
committed by other writers.
<CodeGroup>
```python Python icon="python"
from datetime import timedelta
db = lancedb.connect(uri, read_consistency_interval=timedelta(seconds=5))
```
```typescript TypeScript icon="square-js"
const db = await lancedb.connect(uri, { readConsistencyInterval: 5 });
```
</CodeGroup>
The default reads a snapshot taken when the table was opened, so a long-lived
connection **will not see other processes' writes** until it reopens the table.
That is the right default for a batch job and the wrong one for a service.
Set it when several processes write the same table and readers must observe
those writes. The cost is a metadata check on that interval. See
[Consistency](/tables/consistency).
## Database-level operations {#operations}
| | Python | TypeScript | SQL |
| --- | --- | --- | --- |
| list tables | `table_names`, `list_tables` | `tableNames`, `listTables` | -- |
| the URI it opened | `uri` | `display()` | -- |
| drop every table | `drop_all_tables` | `dropAllTables` | -- |
| drop the database | `drop_database` | -- | -- |
| close | -- | `close`, `isOpen` | -- |
<CodeGroup>
```python Python icon="python"
db.table_names()
tbl = db.open_table("documents")
db.drop_table("documents")
```
```typescript TypeScript icon="square-js"
await db.tableNames();
const tbl = await db.openTable("documents");
await db.dropTable("documents");
```
```sql SQL
DROP TABLE documents;
```
</CodeGroup>
Each takes a `namespace_path` to act inside a [namespace](/management/namespace) rather
than at the root.
<Warning>
`drop_database()` removes every table in the database. There is no confirmation
and no undo -- table [versioning](/management/table#versioning) does not survive the table
being dropped.
</Warning>
## Async connections {#async}
`connect_async` returns an `AsyncConnection` with the same surface as
coroutines. The TypeScript SDK is async throughout, so its `connect` already is
one.
```python
db = await lancedb.connect_async("db://my-database", api_key="...")
tbl = await db.open_table("documents")
```
This is a different axis from the `_async` operations that return a
[job](/basics/jobs): `connect_async` is about not blocking your event loop,
while `create_index_async` is about work that outlives the call.