Supported sources
For PostgreSQL applications, see Search with PostgreSQL and LambdaDB for collection design, search compatibility, and application-owned ingestion. PostgreSQL is not currently a Migration CLI source.
The CLI validates and forwards all 49 fixed analyzer presets. Elasticsearch inventory preserves supported field analyzers and index defaults, and flags custom or unsupported settings for explicit review. Verification searches retain their dense/sparse behavior and do not rerank. See Elasticsearch analyzer mappings.
Migration workflow
- Install the CLI.
- Generate an inventory and editable mapping from the source.
- Review the generated LambdaDB collection and field mapping.
- Run a dry run.
- Run the migration with validation enabled.
- Review the validation report and representative search results.
- Switch production traffic after result quality, latency, and application query rewrites are verified.
Install the CLI
This guide covers v0.1.9. Install the latest stable release below. The executable islambdadb-migration; the general LambdaDB CLI uses lambdadb for JSONL imports and everyday queries.
- Homebrew
- Standalone installer
With Homebrew on macOS or Linux:The public tap installs the released binary without Go or Node. To update:To remove the binary:New GitHub releases may reach the tap later, after the formula is updated.
type -a lambdadb-migration and identify which binary is on PATH. Remove only the old installation using its original method. Do not force-overwrite a Homebrew symlink or run the standalone installer against a Homebrew-managed path. Uninstalling the binary does not remove mappings, checkpoints, or credentials.
Common CLI behavior
LambdaDB Cloud uses region-specific API base URLs. Use your project’s base URL and project name, together with a project API key created in its API Keys tab. Project creation does not automatically issue a key; save the full value when you create it, because it is shown only once. See API key management. Do not assume a global default URL or a fixed project name.
.env files or the general CLI’s saved configuration.
Generated mappings set target.createCollection: true by default. With that setting, the migration creates the LambdaDB collection if it does not already exist, then begins writing documents. The CLI does not poll a collection status; transient write failures use its retry policy.
Use --migration.create-collection=false when the LambdaDB collection already exists and the migration should fail instead of creating it.
The CLI stores local checkpoints under .lambdadb-migration/checkpoints by default. If a migration is interrupted, rerun the same command to resume from the last saved checkpoint. Use --migration.restart to start from the beginning.
A completed checkpoint skips re-reading and uploading documents on rerun. Use --migration.restart to migrate new source data after a completed run. Validation-enabled runs retain sample documents in local checkpoint files so validation can be retried without uploading again; protect these files as source data. If a completed checkpoint has no saved samples, restart to collect them or use --migration.validation-sample-size=0 for count-only validation.
Generate embeddings from migrated text
The Migration CLI supports explicit native embedding configuration underpayload.indexConfigs. Merge the following settings into the payload section of your generated JSON or YAML mapping, preserving its other source, target, and vector settings. This example renames source text source_body to body and adds a separate generated vector field:
sources entry names a destination field after renaming; dotted paths select values inside stored objects. OpenAI models take exactly one text source. A Cohere model combines up to 16 text and image sources, where an image field holds a public HTTPS URL or data URI, or a flat array of them:
dimensions and similarity inside embedding; the CLI inserts no defaults and rejects top-level native dimensions/similarity, embedding.dimensions outside the supported range, and unknown keys in a sources entry during mapping validation. Model, source type, and image limits remain server validations.
Set --migration.write-mode upsert: bulk upsert never generates embeddings. Generation consumes inference usage, including possible repeated provider calls on retries.
Generated inventories preserve stored vectors as ordinary vector fields. Keep those fields separate from generated vectors; a native payload index cannot replace a mapped source vector field. Existing target schemas are not updated or reconciled.
Query-overlap validation continues to use stored dense/sparse vectors. It does not run Bayesian queries, rerank results, or measure generated-vector quality.
Validation
Use--migration.validate for post-migration checks. Validation compares the accepted record count against the source inventory, fetches a sample of migrated documents from LambdaDB with strongly consistent reads, and compares sampled fields.
Use --migration.validation-report to write a JSON report:
--migration.query-overlap compares source and LambdaDB nearest-neighbor results for validation samples. By default, it reports overlap without failing the migration. Set --migration.query-overlap-min-ratio above 0 to require a minimum average overlap. Query-overlap validation is not implemented for Elasticsearch yet.
Next steps
Search with PostgreSQL
Organize tenant, chat, and repository search datasets and review PostgreSQL search compatibility.
Migrate from Qdrant
Move Qdrant collections, points, vectors, sparse vectors, and payload indexes to LambdaDB.
Migrate from Pinecone
Move Pinecone Serverless indexes, namespaces, vectors, and metadata to LambdaDB.
Migrate from Elasticsearch
Move Elasticsearch index mappings, documents, and dense vectors to LambdaDB.
Create a collection
Learn how LambdaDB collection index configurations map to migrated data.
Bulk upsert data
Understand LambdaDB bulk loading behavior for collections with caller-provided vectors.
Hybrid query
Rewrite dense, sparse, and lexical hybrid search after migration.