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A broad documentation pass across the areas LanceDB Enterprise and Embedded diverge on most: **Data Curation** -- GPU Function execution, Slurm scheduling (and what Slurm is, for readers new to it), blob late materialization as its own page, joins, aggregation/profiling, sampling, near-duplicate detection, chunking, distributed shuffle, and IVF-partition clustering. **Feature Engineering** -- computed columns and materialized views, restructured to lead with the Function-based path and show the SQL form side by side with Python throughout; a single Auto Refresh page instead of duplicating scheduling details on every refresh page; adaptive execution; checkpointing; GPU and Slurm placement for refresh workers; a Training Cache page for the PyTorch data loader's automatic cache benefit. **Security & Governance** -- an Audit Log reference (schema, access, grants), Secrets promoted to an ordinary catalog object with their own SQL DDL and a vending/rotation guide, and privilege-table fixes verified against the authorization source. **Deployment & Maintenance** -- Horizontal Scaling and OpenTelemetry moved into a real Deployment area; Automated Cleanup folded into Intelligent Auto-Maintenance (every other maintenance decision already lived there); RTE Compaction and Advanced Conflict Resolution documented in depth. **Landing page** -- the Enterprise feature comparison table reorganized (several redundant or stale rows removed, several new areas added), and the "why Enterprise" bullets replaced with ones tied to a concrete page (Performance, Scale, Fault tolerance, Multicloud deployment, Simplify operations) instead of vague promises. Plus a full pass addressing lancedb-gatekeeper's review: a real test-safety bug (a quickstart test could silently overwrite and delete a deployment's own `frames` table), a fabricated SQL statement with no backing implementation, an actual dedup-guarantee bug in `take_row_ids`, and dozens of documentation-accuracy fixes verified against source rather than taken on faith -- each either fixed, or left with an explicit note on why it needs a feature or deployment owner's sign-off instead of being guessed at. 🤖 Generated with [Claude Code](https://claude.com/claude-code) https://claude.ai/code/session_018PXMCbRH6i5w47TsjeEUMT --------- Co-authored-by: Claude Sonnet 5 <noreply@anthropic.com>
157 lines
5.7 KiB
Plaintext
157 lines
5.7 KiB
Plaintext
---
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title: "Database"
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sidebarTitle: "Database"
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description: "Create, describe, list, attach, and drop databases with SQL."
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icon: database
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keywords: ["database", "create database", "describe database", "show databases", "drop database", "attach database", "sql"]
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availability:
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embedded: unavailable
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enterprise: available
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---
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A database is the catalog's top-level container: it holds
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[namespaces](/sql/ddl/namespace), which hold tables, views and other objects.
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Database statements name one database, independently of the session's
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current database. Database creation uses the deployment's native catalog
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and storage settings.
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## CREATE DATABASE {#create}
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<CodeGroup>
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```sql SQL icon="database"
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CREATE DATABASE analytics
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CREATE DATABASE IF NOT EXISTS "team/search"
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```
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</CodeGroup>
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Creates a persistent database. Requires `CREATE DATABASE` on the system, and
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ownership of the database name if it already has an owner. The caller
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becomes the owner of a new name, following the same rules as the REST API.
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The result has `operation`, `name`, and `status` columns. Status is
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`created`, or `already_exists` with `IF NOT EXISTS`. Without that clause, an
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existing database is an error. Creation never overwrites an existing
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database.
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<Note>
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`WITH` options are unsupported on `CREATE DATABASE`. Use `ATTACH DATABASE`
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[below](#attach) to register a database at an existing location. The
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`system` database and reserved storage names cannot be created.
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</Note>
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## DESCRIBE DATABASE {#describe}
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<CodeGroup>
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```sql SQL icon="database"
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DESCRIBE DATABASE analytics
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DESC DATABASE "team/search"
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```
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</CodeGroup>
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Requires `USAGE` on the database. Returns one row with `name` and
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`properties`. Properties are the catalog's metadata encoded as a JSON
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object; a database without metadata returns `{}`, and a database mid
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`CASCADE` drop reports a transient property marking it as dropping. A
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missing database is an error. `DESCRIBE DATABASE system` returns empty
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properties and requires system `USAGE`.
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## SHOW DATABASES {#show}
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<CodeGroup>
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```sql SQL icon="database"
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SHOW DATABASES
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```
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</CodeGroup>
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Returns a sorted `name` column containing the databases the caller has
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`USAGE` on, including `system` when permitted. `LIKE` and `WHERE` filters
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are unsupported.
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## ATTACH DATABASE {#attach}
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<CodeGroup>
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```sql SQL icon="database"
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ATTACH DATABASE analytics WITH (location = 'analytics')
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ATTACH DATABASE IF NOT EXISTS analytics WITH (location = 'analytics')
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ATTACH DATABASE analytics WITH (location = 's3://customer-bucket/raw/analytics/')
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ATTACH DATABASE analytics WITH (location = 'az://customer-data@customeraccount.blob.core.windows.net/raw/analytics')
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```
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</CodeGroup>
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Registers an existing database at a path relative to the catalog's storage
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root, or at an external S3, GCS or Azure location, instead of creating a
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new one. `location` is the only supported option -- naming a storage
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integration explicitly is refused. For an external location, the
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deployment automatically binds the most specific
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[storage integration](/sql/ddl/storage-integration) whose prefix covers
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it; one must already exist. An Azure location must be account-qualified
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(`az://container@account.blob.core.windows.net/path`); a bare
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`az://container/path` is refused. `ATTACH DATABASE` requires the same
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creation privileges as `CREATE DATABASE`. For an external location, it also
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requires `USAGE` on the storage integration that binds it, and on that
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integration's own database and namespace; the integration itself must live
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in a native, root-backed database under the catalog root.
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Attaching writes Enterprise's own tracking metadata into the location to
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bring it under management -- it does not rewrite, move, or re-encode any
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existing table's data.
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<Warning>
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A relative-path location never accepts an absolute path (`/tmp/db`), a
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`file://` URI, a Windows path (`C:/db`), a `..` segment, an empty string,
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or a doubled slash (`sub//db`). An S3 or GCS location must be a concrete
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prefix, not a bare scheme (`s3://`) on its own.
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</Warning>
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`IF NOT EXISTS` makes the statement a no-op rather than an error when the
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database is already attached.
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<Note>
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A quoted name reaches characters a bare identifier cannot, such as
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`` ATTACH DATABASE "team/search" WITH (location = 'team-search') ``.
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Removing an externally attached database with `DROP DATABASE` unregisters
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the attachment and releases its storage-integration reference, without
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deleting the underlying data.
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</Note>
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## DROP DATABASE {#drop}
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<CodeGroup>
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```sql SQL icon="database"
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DROP DATABASE analytics
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DROP DATABASE IF EXISTS analytics RESTRICT
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DROP DATABASE analytics CASCADE
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```
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</CodeGroup>
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Requires `USAGE` and `OWNERSHIP` on the database. The default, `RESTRICT`,
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refuses a database that still contains objects. `CASCADE` refuses new
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objects in the database, revokes every grant in it, and starts a job that
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drops its contents; deployments without cascade support reject it. An
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externally attached database cannot be dropped with `CASCADE`.
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`RESTRICT` returns `operation`, `name`, and `status` columns: `dropped`, or
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`not_found` with `IF EXISTS` for a missing database. `CASCADE` returns
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`operation`, `job_id`, and `status` columns: the job's id with `dropping`,
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or an empty `job_id` with `not_found`. The name stays taken until the job
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finishes and the dropped storage is cleaned up. The `system` database and
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federated databases cannot be dropped.
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<Note>
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`ALTER DATABASE` is unsupported.
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</Note>
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## What to read next {#next}
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<CardGroup cols={2}>
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<Card title="Namespace" icon="folder-tree" href="/sql/ddl/namespace">
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CREATE SCHEMA inside an attached database.
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</Card>
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<Card title="Table" icon="table" href="/sql/ddl/table">
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Creating tables once a database and namespace exist.
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</Card>
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<Card title="Database" icon="database" href="/management/database">
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The SDK equivalent, and connection settings.
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</Card>
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</CardGroup>
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