mirror of
https://github.com/lancedb/lancedb.git
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Daniel Rammer
a651b67c76
Four of the eight LSM methods are remote-only in the core: `impl BaseTable for NativeTable` implements only set/unset/get_lsm_write_spec and close_lsm_writers, while flush_lsm, compact_lsm and get_lsm_stats fall through to trait defaults returning NotSupported. That is why Node had bound the four that work locally and stopped, and why the remaining four had no binding-level coverage anywhere. Node: add napi bindings for flush_lsm, compact_lsm, checkpoint_lsm and get_lsm_stats, with typed LsmStats/BucketStats/GenerationStats/ MemtableStats objects mirroring the existing LsmWriteSpec object in the same file. Tests assert each binding reaches the core and surfaces NotSupported locally; behavior against a real endpoint stays covered by the mocked-endpoint tests in rust/lancedb/src/remote/table.rs. Python: LsmWriteSpec was importable only from the private lancedb._lancedb -- it appeared in table.py solely under `if TYPE_CHECKING:`. Export it as lancedb.LsmWriteSpec, add it to __all__, and list it in the API reference, which had no mention of it and so rendered it nowhere. Java: add the LSM routes to lancedb-core. Java reaches LanceDB purely over REST through the generated namespace client, and these routes are not in the Lance Namespace spec, so they are issued through a small dedicated client. LsmWriteSpec is deliberately not org.lance.memwal. InitializeMemWalParams: that type defaults to maintaining no indexes where a spec here defaults to maintaining every index, and it cannot express the null that asks the server to resolve the set. checkpointLsm is ported from rust/lancedb/src/table/checkpoint.rs with its constants and status semantics intact -- 429/503 retried in place, 421 restarting from flush. Note: `mvnw spotless:apply` cannot run on JDK 21 (google-java-format 1.7, pinned in java/pom.xml, predates JDK 16's compiler API change). This is pre-existing and reproduces on a pristine main checkout; the Java sources here were formatted by hand to the checkstyle rules. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
86 lines
2.2 KiB
Markdown
86 lines
2.2 KiB
Markdown
# LanceDB Java Enterprise Client
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## Configuration and Initialization
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### LanceDB Cloud
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For LanceDB Cloud, use the simplified builder API:
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```java
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import com.lancedb.LanceDbNamespaceClientBuilder;
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import org.lance.namespace.LanceNamespace;
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// If your DB url is db://example-db, then your database here is example-db
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LanceNamespace namespaceClient = LanceDbNamespaceClientBuilder.newBuilder()
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.apiKey("your_lancedb_cloud_api_key")
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.database("your_database_name")
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.build();
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```
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### LanceDB Enterprise
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For Enterprise deployments, use your custom endpoint:
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```java
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LanceNamespace namespaceClient = LanceDbNamespaceClientBuilder.newBuilder()
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.apiKey("your_lancedb_enterprise_api_key")
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.database("your_database_name")
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.endpoint("<your_enterprise_endpoint>")
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.build();
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```
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## MemWAL LSM write path
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Most table operations reach LanceDB through the `LanceNamespace` above, which is
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generated from the Lance Namespace specification. The MemWAL LSM routes are not part
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of that specification, so they are issued through a separate client:
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```java
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import com.lancedb.LanceDbRestClient;
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import com.lancedb.LanceDbTableLsm;
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import com.lancedb.LsmWriteSpec;
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LanceDbRestClient client = LanceDbNamespaceClientBuilder.newBuilder()
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.apiKey("your_lancedb_cloud_api_key")
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.database("your_database_name")
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.buildRestClient();
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LanceDbTableLsm lsm = new LanceDbTableLsm(client, "my_table");
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// Route future merge_insert upserts through the MemWAL, hash-bucketed by `id`.
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lsm.setLsmWriteSpec(LsmWriteSpec.bucket("id", 16));
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// ... merge_insert traffic ...
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// Converge the fresh tier into the base table.
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lsm.checkpointLsm();
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// Inspect live per-bucket state.
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lsm.getLsmStats().ifPresent(stats -> System.out.println(stats.get("buckets")));
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client.close();
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```
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`maintainedIndexes` is tri-state, and the null default is the opposite of what a Java
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reader usually expects:
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| Value | Meaning |
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| --- | --- |
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| unset (null) | Maintain **every** index the MemWAL can, resolved on install |
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| `Collections.emptyList()` | Maintain **none** |
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| `Arrays.asList("id_idx")` | Maintain exactly those |
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## Development
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Build:
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```shell
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./mvnw install -pl lancedb-core -am
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```
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Run tests:
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```shell
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./mvnw test -pl lancedb-core
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```
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