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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>
58 lines
1.9 KiB
Plaintext
58 lines
1.9 KiB
Plaintext
---
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title: "JSON functions"
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sidebarTitle: "JSON Functions"
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description: "json_get and its typed variants, json_extract, and the rest of Lance's JSON accessor functions."
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icon: brackets-curly
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keywords: ["json_get", "json_extract", "json", "sql", "scalar function"]
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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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| Function | Returns |
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| --- | --- |
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| `json_get(col, key)` | the value at `key`, still JSON |
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| `json_get_string(col, key)` | `Utf8` |
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| `json_get_int(col, key)` | `Int64` |
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| `json_get_float(col, key)` | `Float64` |
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| `json_get_bool(col, key)` | `Boolean` |
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| `json_extract(col, path)` | `Utf8`: the value as JSON text, by path |
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| `json_extract_with_type(col, path)` | a struct of the value as JSON and a type tag, by path |
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| `json_exists(col, path)` | `Boolean` |
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| `json_array_contains(col, value)` | `Boolean` |
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| `json_array_length(col)` | length |
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`json_get` returns JSON, so a typed accessor can read a field inside it:
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<CodeGroup>
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```sql SQL icon="database"
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SELECT * FROM events
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WHERE json_get_string(json_get(data, 'user'), 'name') = 'Alice'
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```
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</CodeGroup>
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That works one level down. A `json_get` nested inside another `json_get` is
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refused, so reach a deeper value with `json_extract` and a JSONPath instead. It
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returns JSON text, so a string compares with its quotes:
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<CodeGroup>
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```sql SQL icon="database"
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SELECT * FROM events
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WHERE json_extract(data, '$.user.profile.name') = '"Alice"'
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```
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</CodeGroup>
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**`json_get`, its typed variants, and `json_extract` are index-accelerated** by a
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JSON scalar index on the column. The rest evaluate per row.
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## What to read next {#next}
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<CardGroup cols={2}>
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<Card title="JSON data type" icon="brackets-curly" href="/sql/data-types#json">
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How a JSON column is stored, and reading it as a typed value.
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</Card>
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<Card title="CREATE INDEX" icon="bolt" href="/sql/ddl/index">
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Build the scalar index that accelerates `json_get` and `json_extract`.
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</Card>
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</CardGroup>
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