Curate datasets

Data curation with LaminDB ensures your datasets are validated and queryable. This guide shows you how to transform data into clean, annotated datasets.

Curating a dataset with LaminDB means three things:

  • Validate that the dataset matches a desired schema.

  • Standardize the dataset (e.g., by fixing typos, mapping synonyms) or update registries if validation fails.

  • Annotate the dataset by linking it against metadata entities so that it becomes queryable.

In this guide we’ll curate common data structures. Here is a guide for the underlying low-level API.

Note: If you know either pydantic or pandera, here is an FAQ that compares LaminDB with both of these tools.

# pip install 'lamindb[bionty]'
!lamin init --storage ./test-curate --modules bionty
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 initialized lamindb: testuser1/test-curate
import lamindb as ln

ln.track("MCeA3reqZG2e")
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 connected lamindb: testuser1/test-curate
 created Transform('MCeA3reqZG2e0000'), started new Run('dkKysAvh...') at 2025-07-21 11:33:08 UTC
 notebook imports: lamindb==1.9.0

Schema design patterns

A Schema in LaminDB is a specification that defines the expected structure, data types, and validation rules for a dataset. It is similar to pydantic.Model for dictionaries, and pandera.Schema, and pyarrow.lib.Schema for tables, but supporting more complicated data structures.

Schemas ensure data consistency by defining:

  • What Features (dimensions) exist in your dataset

  • What data types those features should have

  • What values are valid for categorical features

  • Which Features are required vs optional

Key components of a schema:

schema = ln.Schema(
    name="experiment_schema",           # human-readable name
    features=[                          # required features
        ln.Feature(name="cell_type", dtype=bt.CellType),
        ln.Feature(name="treatment", dtype=str),
    ],
    flexible=True,                      # allow additional features?
    otype="DataFrame"                   # object type (DataFrame, AnnData, etc.)
)

For complex data structures:

# AnnData with multiple "slots"
adata_schema = ln.Schema(
    otype="AnnData",
    slots={
        "obs": cell_metadata_schema,     # cell annotations
        "var.T": gene_id_schema          # gene-derived features  
    }
)

Before diving into curation, let’s understand the different schema approaches and when to use each one. Think of schemas as rules that define what valid data should look like.

Flexible schema

Use when: You want to validate against your existing feature registry without strict requirements.

import lamindb as ln

schema = ln.Schema(name="valid_features", itype=ln.Feature).save()

Minimal required schema

Use when: You need certain columns but want flexibility for additional metadata.

import lamindb as ln

schema = ln.Schema(
    name="Mini immuno schema",
    features=[
        ln.Feature.get(name="perturbation"),
        ln.Feature.get(name="cell_type_by_model"),
        ln.Feature.get(name="assay_oid"),
        ln.Feature.get(name="donor"),
        ln.Feature.get(name="concentration"),
        ln.Feature.get(name="treatment_time_h"),
    ],
    flexible=True,  # _additional_ columns in a dataframe are validated & annotated
).save()

Strict Schema

Use when: You need complete control over data structure and values.

# Only allows specified columns
schema = ln.Schema(
    features=[...],
    minimal_set=True,  # whether all passed features are required
    maximal_set=False  # whether additional features are allowed
)

DataFrame

Step 1: Load and examine your data

We’ll be working with the mini immuno dataset:

df = ln.core.datasets.mini_immuno.get_dataset1(
    with_cell_type_synonym=True, with_cell_type_typo=True
)
df
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ENSG00000153563 ENSG00000010610 ENSG00000170458 perturbation sample_note cell_type_by_expert cell_type_by_model assay_oid concentration treatment_time_h donor donor_ethnicity
sample1 1 3 5 DMSO was ok B-cell B cell EFO:0008913 0.1% 24 D0001 [Chinese, Singaporean Chinese]
sample2 2 4 6 IFNG looks naah CD8-pos alpha-beta T cell T cell EFO:0008913 200 nM 24 D0002 [Chinese, Han Chinese]
sample3 3 5 7 DMSO pretty! 🤩 CD8-pos alpha-beta T cell T cell EFO:0008913 0.1% 6 None [Chinese]

Step 2: Set up your metadata registries

Before creating a schema, ensure your registries have the right features and labels:

import lamindb as ln
import bionty as bt

# define valid labels
perturbation_type = ln.ULabel(name="Perturbation", is_type=True).save()
ln.ULabel(name="DMSO", type=perturbation_type).save()
ln.ULabel(name="IFNG", type=perturbation_type).save()
bt.CellType.from_source(name="B cell").save()
bt.CellType.from_source(name="T cell").save()

# define valid features
ln.Feature(name="perturbation", dtype=perturbation_type).save()
ln.Feature(name="cell_type_by_expert", dtype=bt.CellType).save()
ln.Feature(name="cell_type_by_model", dtype=bt.CellType).save()
ln.Feature(name="assay_oid", dtype=bt.ExperimentalFactor.ontology_id).save()
ln.Feature(name="concentration", dtype=str).save()
ln.Feature(name="treatment_time_h", dtype="num", coerce_dtype=True).save()
ln.Feature(name="donor", dtype=str, nullable=True).save()
ln.Feature(name="donor_ethnicity", dtype=list[bt.Ethnicity]).save()

Step 3: Create your schema

schema = ln.core.datasets.mini_immuno.define_mini_immuno_schema_flexible()
schema.describe()
Schema 
├── .uid = 'gZrlBlymjkeqAN4C'
├── .name = 'Mini immuno schema'
├── .itype = 'Feature'
├── .ordered_set = False
├── .maximal_set = False
├── .minimal_set = True
├── .created_by = testuser1 (Test User1)
├── .created_at = 2025-07-21 11:33:11
└── Feature6
    └── name               dtype                                      optional  nullab…  coerce_dtype  default_val…
        perturbation       cat[ULabel[Perturbation]]                  ✗         ✓        ✗             unset       
        cell_type_by_mod…  cat[bionty.CellType]                       ✗         ✓        ✗             unset       
        assay_oid          cat[bionty.ExperimentalFactor.ontology_i…  ✗         ✓        ✗             unset       
        donor              str                                        ✗         ✓        ✗             unset       
        concentration      str                                        ✗         ✓        ✗             unset       
        treatment_time_h   num                                        ✗         ✓        ✓             unset       

Step 4: Initialize Curator and first validation

If you expect the validation to pass, you can directly register an artifact by providing the schema:


artifact = ln.Artifact.from_df(df, key="examples/my_curated_dataset.parquet", schema=schema).save()

The validate() method validates that your dataset adheres to the criteria defined by the schema. It identifies which values are already validated (exist in the registries) and which are potentially problematic (do not yet exist in our registries).

try:
    curator = ln.curators.DataFrameCurator(df, schema)
    curator.validate()
except ln.errors.ValidationError as error:
    print(error)
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! 4 terms not validated in feature 'columns': 'ENSG00000153563', 'ENSG00000010610', 'ENSG00000170458', 'sample_note'
    → fix typos, remove non-existent values, or save terms via: curator.cat.add_new_from('columns')
! 2 terms not validated in feature 'cell_type_by_expert': 'B-cell', 'CD8-pos alpha-beta T cell'
    1 synonym found: "B-cell" → "B cell"
    → curate synonyms via: .standardize("cell_type_by_expert")
    for remaining terms:
    → fix typos, remove non-existent values, or save terms via: curator.cat.add_new_from('cell_type_by_expert')
2 terms not validated in feature 'cell_type_by_expert': 'B-cell', 'CD8-pos alpha-beta T cell'
    1 synonym found: "B-cell" → "B cell"
    → curate synonyms via: .standardize("cell_type_by_expert")
    for remaining terms:
    → fix typos, remove non-existent values, or save terms via: curator.cat.add_new_from('cell_type_by_expert')

Step 5: Fix validation issues

# check the non-validated terms
curator.cat.non_validated
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{'cell_type_by_expert': ['B-cell', 'CD8-pos alpha-beta T cell']}

For cell_type_by_expert, we saw 2 terms are not validated.

First, let’s standardize synonym “B-cell” as suggested

curator.cat.standardize("cell_type_by_expert")
# now we have only one non-validated cell type left
curator.cat.non_validated
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{'cell_type_by_expert': ['CD8-pos alpha-beta T cell']}

For “CD8-pos alpha-beta T cell”, let’s understand which cell type in the public ontology might be the actual match.

# to check the correct spelling of categories, pass `public=True` to get a lookup object from public ontologies
# use `lookup = curator.cat.lookup()` to get a lookup object of existing records in your instance
lookup = curator.cat.lookup(public=True)
lookup
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Lookup objects from the public:
 .perturbation
 .cell_type_by_expert
 .cell_type_by_model
 .assay_oid
 .donor_ethnicity
 .columns
 
Example:
    → categories = curator.lookup()["cell_type"]
    → categories.alveolar_type_1_fibroblast_cell

To look up public ontologies, use .lookup(public=True)
# here is an example for the "cell_type" column
cell_types = lookup["cell_type_by_expert"]
cell_types.cd8_positive_alpha_beta_t_cell
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CellType(ontology_id='CL:0000625', name='CD8-positive, alpha-beta T cell', definition='A T Cell Expressing An Alpha-Beta T Cell Receptor And The Cd8 Coreceptor.', synonyms='CD8-positive, alpha-beta T-cell|CD8-positive, alpha-beta T lymphocyte|CD8-positive, alpha-beta T-lymphocyte', parents=array(['CL:0000791'], dtype=object))
# fix the cell type name
df["cell_type_by_expert"] = df["cell_type_by_expert"].cat.rename_categories(
    {"CD8-pos alpha-beta T cell": cell_types.cd8_positive_alpha_beta_t_cell.name}
)

For perturbation, we want to add the new values: “DMSO”, “IFNG”

# this adds perturbations that were _not_ validated
curator.cat.add_new_from("perturbation")
# validate again
curator.validate()
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! 4 terms not validated in feature 'columns': 'ENSG00000153563', 'ENSG00000010610', 'ENSG00000170458', 'sample_note'
    → fix typos, remove non-existent values, or save terms via: curator.cat.add_new_from('columns')

Step 6: Save your curated dataset

artifact = curator.save_artifact(key="examples/my_curated_dataset.parquet")
artifact.describe()
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Artifact .parquet · DataFrame · dataset
├── General
│   ├── key: examples/my_curated_dataset.parquet
│   ├── uid: a2eB7NtWtbh6M2sU0000          hash: 9p8ssBs4kmrjbP6cPCeeaQ
│   ├── size: 9.6 KB                       transform: curate.ipynb
│   ├── space: all                         branch: all
│   ├── created_by: testuser1              created_at: 2025-07-21 11:33:14
│   ├── n_observations: 3
│   └── storage path: /home/runner/work/lamindb/lamindb/docs/test-curate/examples/my_curated_dataset.parquet
├── Dataset features
│   └── columns8                     [Feature]                                                                  
assay_oid                       cat[bionty.ExperimentalFactor.on…  single-cell RNA sequencing              
cell_type_by_expert             cat[bionty.CellType]               B cell, CD8-positive, alpha-beta T cell 
cell_type_by_model              cat[bionty.CellType]               B cell, T cell                          
donor_ethnicity                 list[cat[bionty.Ethnicity]]        Chinese, Han Chinese, Singaporean Chine…
perturbation                    cat[ULabel[Perturbation]]          DMSO, IFNG                              
concentration                   str                                                                        
treatment_time_h                num                                                                        
donor                           str                                                                        
└── Labels
    └── .cell_types                     bionty.CellType                    B cell, T cell, CD8-positive, alpha-bet…
        .experimental_factors           bionty.ExperimentalFactor          single-cell RNA sequencing              
        .ethnicities                    bionty.Ethnicity                   Chinese, Singaporean Chinese, Han Chine…
        .ulabels                        ULabel                             DMSO, IFNG                              

Common fixes

This section covers the most frequent curation issues and their solutions. Use this as a reference when validation fails.

Feature validation issues

Issue: “Column not in dataframe”

"column 'treatment' not in dataframe. Columns in dataframe: ['drug', 'timepoint', ...]"

Solutions:

# Solution 1: Rename columns to match schema
df = df.rename(columns={
    'treatment': 'drug',
    'time': 'timepoint',
    ...
})

# Solution 2: Create missing columns
df['treatment'] = 'unknown'  # Add with default value (or define Feature.default_value)

# Solution 3: Modify schema to match your data
schema = ln.Schema(
    features=[
        ln.Feature.get(name="drug"),  # Use actual column name
        ln.Feature.get(name="timepoint"),
    ],
    ...
)

Value validation issues

Issue: “Terms not validated in feature ‘perturbation’”

2 terms not validated in feature 'cell_type': 'B-cell', 'CD8-pos alpha-beta T cell'
    1 synonym found: "B-cell" → "B cell"
    → curate synonyms via: .standardize("cell_type")
    for remaining terms:
    → fix typos, remove non-existent values, or save terms via: curator.cat.add_new_from('cell_type')

Solutions:

# Solution 1: Use automatic standardization if given hint (handles synonyms))
curator.cat.standardize('cell_type')

# Solution 2: Manual mapping for complex cases
value_mapping = {
    'T-cells': 'T cell',
    'B-cells': 'B cell',
}
df['cell_type'] = df['cell_type'].map(value_mapping).fillna(df['cell_type'])

# Solution 3: Use public ontology lookup for correct names
lookup = curator.cat.lookup(public=True)
cell_types = lookup["cell_type"]
df['cell_type'] = df['cell_type'].cat.rename_categories({
    'CD8-pos T cell': cell_types.cd8_positive_alpha_beta_t_cell.name
})

# Solution 4: Add new legitimate terms
curator.cat.add_new_from("cell_type")

Data type issues

Issue: “Expected categorical data, got object”

TypeError: Expected categorical data for cell_type, got object

Solutions:

# Solution 1: Convert to categorical
df['cell_type'] = df['cell_type'].astype('category')

# Solution 2: Use coercion in feature definition
ln.Feature(name="cell_type", dtype=bt.CellType, coerce_dtype=True).save()

AnnData

AnnData like all other data structures that follow is a composite structure that stores different arrays in different slots.

Allow a flexible schema

We can also allow a flexible schema for an AnnData and only require that it’s indexed with Ensembl gene IDs.

curate_anndata_flexible.py
import lamindb as ln

ln.core.datasets.mini_immuno.define_features_labels()
adata = ln.core.datasets.mini_immuno.get_dataset1(otype="AnnData")
schema = ln.examples.schemas.anndata_ensembl_gene_ids_and_valid_features_in_obs()
artifact = ln.Artifact.from_anndata(
    adata, key="examples/mini_immuno.h5ad", schema=schema
).save()
artifact.describe()

Let’s run the script.

!python scripts/curate_anndata_flexible.py
Hide code cell output
 connected lamindb: testuser1/test-curate
 returning existing ULabel record with same name: 'Perturbation'
 returning existing ULabel record with same name: 'DMSO'
 returning existing ULabel record with same name: 'IFNG'
 returning existing Feature record with same name: 'perturbation'
 returning existing Feature record with same name: 'cell_type_by_expert'
 returning existing Feature record with same name: 'cell_type_by_model'
 returning existing Feature record with same name: 'assay_oid'
 returning existing Feature record with same name: 'concentration'
 returning existing Feature record with same name: 'treatment_time_h'
 returning existing Feature record with same name: 'donor'
 returning existing Feature record with same name: 'donor_ethnicity'
 connected lamindb: testuser1/test-curate
 connected lamindb: testuser1/test-curate
! no run & transform got linked, call `ln.track()` & re-run
! 1 term not validated in feature 'columns' in slot 'obs': 'sample_note'
    → fix typos, remove non-existent values, or save terms via: curator.slots['obs'].cat.add_new_from('columns')
Artifact .h5ad · AnnData · dataset
├── General
│   ├── key: examples/mini_immuno.h5ad
│   ├── uid: Grn8txiA7im2wuhC0000          hash: FB3CeMjmg1ivN6HDy6wsSg
│   ├── size: 30.9 KB                      transform: None
│   ├── space: all                         branch: all
│   ├── created_by: testuser1              created_at: 2025-07-21 11:33:27
│   ├── n_observations: 3
│   └── storage path: 
/home/runner/work/lamindb/lamindb/docs/test-curate/examples/mini_immuno.
h5ad
├── Dataset features
│   ├── obs7             [Feature]                                           
│   │   assay_oid           cat[bionty.Experiment…  single-cell RNA sequencing  
│   │   cell_type_by_expe…  cat[bionty.CellType]    B cell, CD8-positive, alpha…
│   │   cell_type_by_model  cat[bionty.CellType]    B cell, T cell              
│   │   perturbation        cat[ULabel[Perturbati…  DMSO, IFNG                  
│   │   concentration       str                                                 
│   │   treatment_time_h    num                                                 
│   │   donor               str                                                 
│   └── var.T3           [bionty.Gene.ensembl_…                              
CD8A                num                                                 
CD4                 num                                                 
CD14                num                                                 
└── Labels
    └── .cell_types         bionty.CellType         B cell, T cell, CD8-positiv…
        .experimental_fac…  bionty.ExperimentalFa…  single-cell RNA sequencing  
        .ulabels            ULabel                  DMSO, IFNG                  

Under-the-hood, this used the following schema:

import lamindb as ln
import bionty as bt

obs_schema = ln.examples.schemas.valid_features()
varT_schema = ln.Schema(
    name="valid_ensembl_gene_ids", itype=bt.Gene.ensembl_gene_id
).save()
schema = ln.Schema(
    name="anndata_ensembl_gene_ids_and_valid_features_in_obs",
    otype="AnnData",
    slots={"obs": obs_schema, "var.T": varT_schema},
).save()

This schema tranposes the var DataFrame during curation, so that one validates and annotates the var.T schema, i.e., [ENSG00000153563, ENSG00000010610, ENSG00000170458]. If one doesn’t transpose, one would annotate with the schema of var, i.e., [gene_symbol, gene_type].

https://lamin-site-assets.s3.amazonaws.com/.lamindb/gLyfToATM7WUzkWW0001.png

Fix validation issues

import lamindb as ln
adata = ln.core.datasets.mini_immuno.get_dataset1(
    with_gene_typo=True, with_cell_type_typo=True, otype="AnnData"
)
adata
Hide code cell output
AnnData object with n_obs × n_vars = 3 × 3
    obs: 'perturbation', 'sample_note', 'cell_type_by_expert', 'cell_type_by_model', 'assay_oid', 'concentration', 'treatment_time_h', 'donor'
    uns: 'temperature', 'experiment', 'date_of_study', 'study_note'
Hide code cell content
schema = ln.examples.schemas.anndata_ensembl_gene_ids_and_valid_features_in_obs()
schema.describe()
Schema(uid='0000000000000002', name='anndata_ensembl_gene_ids_and_valid_features_in_obs', n=-1, is_type=False, itype='Composite', otype='AnnData', dtype='num', hash='GTxxM36n9tocphLfdbNt9g', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:23 UTC)
    obs: Schema(uid='0000000000000000', name='valid_features', n=-1, is_type=False, itype='Feature', hash='kMi7B_N88uu-YnbTLDU-DA', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:23 UTC)
    var.T: Schema(uid='0000000000000001', name='valid_ensembl_gene_ids', n=-1, is_type=False, itype='bionty.Gene.ensembl_gene_id', dtype='num', hash='1gocc_TJ1RU2bMwDRK-WUA', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:23 UTC)

Check the slots of a schema:

schema.slots
Hide code cell output
{'obs': Schema(uid='0000000000000000', name='valid_features', n=-1, is_type=False, itype='Feature', hash='kMi7B_N88uu-YnbTLDU-DA', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:23 UTC),
 'var.T': Schema(uid='0000000000000001', name='valid_ensembl_gene_ids', n=-1, is_type=False, itype='bionty.Gene.ensembl_gene_id', dtype='num', hash='1gocc_TJ1RU2bMwDRK-WUA', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:23 UTC)}
curator = ln.curators.AnnDataCurator(adata, schema)
try:
    curator.validate()
except ln.errors.ValidationError as error:
    print(error)
Hide code cell output
! 1 term not validated in feature 'columns' in slot 'obs': 'sample_note'
    → fix typos, remove non-existent values, or save terms via: curator.slots['obs'].cat.add_new_from('columns')
! 1 term not validated in feature 'cell_type_by_expert' in slot 'obs': 'CD8-pos alpha-beta T cell'
    → fix typos, remove non-existent values, or save terms via: curator.slots['obs'].cat.add_new_from('cell_type_by_expert')
1 term not validated in feature 'cell_type_by_expert' in slot 'obs': 'CD8-pos alpha-beta T cell'
    → fix typos, remove non-existent values, or save terms via: curator.slots['obs'].cat.add_new_from('cell_type_by_expert')

As above, we leverage a lookup object with valid cell types to find the correct name.

valid_cell_types = curator.slots["obs"].cat.lookup()["cell_type_by_expert"]
adata.obs["cell_type_by_expert"] = adata.obs[
    "cell_type_by_expert"
].cat.rename_categories(
    {"CD8-pos alpha-beta T cell": valid_cell_types.cd8_positive_alpha_beta_t_cell.name}
)

The validated AnnData can be subsequently saved as an Artifact:

adata.obs.columns
Index(['perturbation', 'sample_note', 'cell_type_by_expert',
       'cell_type_by_model', 'assay_oid', 'concentration', 'treatment_time_h',
       'donor'],
      dtype='object')
curator.slots["var.T"].cat.add_new_from("columns")
! using default organism = human
! 1 term not validated in feature 'columns' in slot 'var.T': 'GeneTypo'
    → fix typos, remove non-existent values, or save terms via: curator.slots['var.T'].cat.add_new_from('columns')
curator.validate()
! 1 term not validated in feature 'columns' in slot 'obs': 'sample_note'
    → fix typos, remove non-existent values, or save terms via: curator.slots['obs'].cat.add_new_from('columns')
artifact = curator.save_artifact(key="examples/my_curated_anndata.h5ad")
Hide code cell output
 returning existing schema with same hash: Schema(uid='45LX4dSpkPD2DgnO', n=7, is_type=False, itype='Feature', hash='cz3FabHcc9Hn61GejKrL8Q', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:27 UTC)

Access the schema for each slot:

artifact.features.slots
Hide code cell output
{'obs': Schema(uid='45LX4dSpkPD2DgnO', n=7, is_type=False, itype='Feature', hash='cz3FabHcc9Hn61GejKrL8Q', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:27 UTC),
 'var.T': Schema(uid='luDCbRUBRB31k2I5', n=3, is_type=False, itype='bionty.Gene.ensembl_gene_id', dtype='num', hash='8e68Zm15DA4DuC39LJr6JA', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, run_id=1, created_at=2025-07-21 11:33:40 UTC)}

The saved artifact has been annotated with validated features and labels:

artifact.describe()
Hide code cell output
Artifact .h5ad · AnnData · dataset
├── General
│   ├── key: examples/my_curated_anndata.h5ad
│   ├── uid: B5QzfERBe5gLi9as0000          hash: yeNWx0-dOGGkANQbocU4Sg
│   ├── size: 30.9 KB                      transform: curate.ipynb
│   ├── space: all                         branch: all
│   ├── created_by: testuser1              created_at: 2025-07-21 11:33:40
│   ├── n_observations: 3
│   └── storage path: /home/runner/work/lamindb/lamindb/docs/test-curate/examples/my_curated_anndata.h5ad
├── Dataset features
│   ├── obs7                         [Feature]                                                                  
│   │   assay_oid                       cat[bionty.ExperimentalFactor.on…  single-cell RNA sequencing              
│   │   cell_type_by_expert             cat[bionty.CellType]               B cell, CD8-positive, alpha-beta T cell 
│   │   cell_type_by_model              cat[bionty.CellType]               B cell, T cell                          
│   │   perturbation                    cat[ULabel[Perturbation]]          DMSO, IFNG                              
│   │   concentration                   str                                                                        
│   │   treatment_time_h                num                                                                        
│   │   donor                           str                                                                        
│   └── var.T3                       [bionty.Gene.ensembl_gene_id]                                              
CD8A                            num                                                                        
CD4                             num                                                                        
└── Labels
    └── .cell_types                     bionty.CellType                    B cell, T cell, CD8-positive, alpha-bet…
        .experimental_factors           bionty.ExperimentalFactor          single-cell RNA sequencing              
        .ulabels                        ULabel                             DMSO, IFNG                              

MuData

curate_mudata.py
import lamindb as ln
import bionty as bt


# define the global obs schema
obs_schema = ln.Schema(
    name="mudata_papalexi21_subset_obs_schema",
    features=[
        ln.Feature(name="perturbation", dtype="cat[ULabel[Perturbation]]").save(),
        ln.Feature(name="replicate", dtype="cat[ULabel[Replicate]]").save(),
    ],
).save()

# define the ['rna'].obs schema
obs_schema_rna = ln.Schema(
    name="mudata_papalexi21_subset_rna_obs_schema",
    features=[
        ln.Feature(name="nCount_RNA", dtype=int).save(),
        ln.Feature(name="nFeature_RNA", dtype=int).save(),
        ln.Feature(name="percent.mito", dtype=float).save(),
    ],
).save()

# define the ['hto'].obs schema
obs_schema_hto = ln.Schema(
    name="mudata_papalexi21_subset_hto_obs_schema",
    features=[
        ln.Feature(name="nCount_HTO", dtype=int).save(),
        ln.Feature(name="nFeature_HTO", dtype=int).save(),
        ln.Feature(name="technique", dtype=bt.ExperimentalFactor).save(),
    ],
).save()

# define ['rna'].var schema
var_schema_rna = ln.Schema(
    name="mudata_papalexi21_subset_rna_var_schema",
    itype=bt.Gene.symbol,
    dtype=float,
).save()

# define composite schema
mudata_schema = ln.Schema(
    name="mudata_papalexi21_subset_mudata_schema",
    otype="MuData",
    slots={
        "obs": obs_schema,
        "rna:obs": obs_schema_rna,
        "hto:obs": obs_schema_hto,
        "rna:var": var_schema_rna,
    },
).save()

# curate a MuData
mdata = ln.core.datasets.mudata_papalexi21_subset()
bt.settings.organism = "human"  # set the organism to map gene symbols
curator = ln.curators.MuDataCurator(mdata, mudata_schema)
artifact = curator.save_artifact(key="examples/mudata_papalexi21_subset.h5mu")
assert artifact.schema == mudata_schema
!python scripts/curate_mudata.py
Hide code cell output
 connected lamindb: testuser1/test-curate
 returning existing Feature record with same name: 'perturbation'
! you are trying to create a record with name='nFeature_HTO' but a record with similar name exists: 'nFeature_RNA'. Did you mean to load it?
! auto-transposed `var` for backward compat, please indicate transposition in the schema definition by calling out `.T`: slots={'var.T': itype=bt.Gene.ensembl_gene_id}
! 37 terms not validated in feature 'columns': 'adt:G2M.Score', 'adt:HTO_classification', 'adt:MULTI_ID', 'adt:NT', 'adt:Phase', 'adt:S.Score', 'adt:gene_target', 'adt:guide_ID', 'adt:orig.ident', 'adt:percent.mito', 'adt:perturbation', 'adt:replicate', 'hto:G2M.Score', 'hto:HTO_classification', 'hto:MULTI_ID', 'hto:NT', 'hto:Phase', 'hto:S.Score', 'hto:gene_target', 'hto:guide_ID', ...
    → fix typos, remove non-existent values, or save terms via: curator.cat.add_new_from('columns')
! 2 terms not validated in feature 'perturbation': 'Perturbed', 'NT'
    → fix typos, remove non-existent values, or save terms via: curator.cat.add_new_from('perturbation')
    → a valid label for subtype 'Perturbation' has to be one of ['DMSO', 'IFNG']
lamindb.models.ulabel.ULabel.DoesNotExist

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/home/runner/work/lamindb/lamindb/docs/scripts/curate_mudata.py", line 57, in <module>
    artifact = curator.save_artifact(key="examples/mudata_papalexi21_subset.h5mu")
  File "/home/runner/work/lamindb/lamindb/lamindb/curators/core.py", line 335, in save_artifact
    self.validate()
  File "/home/runner/work/lamindb/lamindb/lamindb/curators/core.py", line 320, in validate
    curator.validate()
  File "/home/runner/work/lamindb/lamindb/lamindb/curators/core.py", line 658, in validate
    self._cat_manager_validate()
  File "/home/runner/work/lamindb/lamindb/lamindb/curators/core.py", line 642, in _cat_manager_validate
    self.cat.validate()
  File "/home/runner/work/lamindb/lamindb/lamindb/curators/core.py", line 1510, in validate
    cat_vector.validate()
  File "/home/runner/work/lamindb/lamindb/lamindb/curators/core.py", line 1352, in validate
    self._validated, self._non_validated = self._add_validated()
  File "/home/runner/work/lamindb/lamindb/lamindb/curators/core.py", line 1169, in _add_validated
    type_record = registry.get(name=self._subtype_str)
  File "/home/runner/work/lamindb/lamindb/lamindb/models/sqlrecord.py", line 465, in get
    return QuerySet(model=cls).get(idlike, **expressions)
  File "/home/runner/work/lamindb/lamindb/lamindb/models/query_set.py", line 873, in get
    record = get(self, idlike, **expressions)
  File "/home/runner/work/lamindb/lamindb/lamindb/models/query_set.py", line 226, in get
    raise registry.DoesNotExist from registry.DoesNotExist
lamindb.models.ulabel.ULabel.DoesNotExist

SpatialData

define_schema_spatialdata.py
import lamindb as ln
import bionty as bt


attrs_schema = ln.Schema(
    features=[
        ln.Feature(name="bio", dtype=dict).save(),
        ln.Feature(name="tech", dtype=dict).save(),
    ],
).save()

sample_schema = ln.Schema(
    features=[
        ln.Feature(name="disease", dtype=bt.Disease, coerce_dtype=True).save(),
        ln.Feature(
            name="developmental_stage",
            dtype=bt.DevelopmentalStage,
            coerce_dtype=True,
        ).save(),
    ],
).save()

tech_schema = ln.Schema(
    features=[
        ln.Feature(name="assay", dtype=bt.ExperimentalFactor, coerce_dtype=True).save(),
    ],
).save()

obs_schema = ln.Schema(
    features=[
        ln.Feature(name="sample_region", dtype="str").save(),
    ],
).save()

# Schema enforces only registered Ensembl Gene IDs are valid (maximal_set=True)
varT_schema = ln.Schema(itype=bt.Gene.ensembl_gene_id, maximal_set=True).save()

sdata_schema = ln.Schema(
    name="spatialdata_blobs_schema",
    otype="SpatialData",
    slots={
        "attrs:bio": sample_schema,
        "attrs:tech": tech_schema,
        "attrs": attrs_schema,
        "tables:table:obs": obs_schema,
        "tables:table:var.T": varT_schema,
    },
).save()
!python scripts/define_schema_spatialdata.py
Hide code cell output
 connected lamindb: testuser1/test-curate
! you are trying to create a record with name='tech' but a record with similar name exists: 'technique'. Did you mean to load it?
! you are trying to create a record with name='assay' but a record with similar name exists: 'assay_oid'. Did you mean to load it?
curate_spatialdata.py
import lamindb as ln

spatialdata = ln.core.datasets.spatialdata_blobs()
sdata_schema = ln.Schema.get(name="spatialdata_blobs_schema")
curator = ln.curators.SpatialDataCurator(spatialdata, sdata_schema)
try:
    curator.validate()
except ln.errors.ValidationError:
    pass

spatialdata.tables["table"].var.drop(index="ENSG00000999999", inplace=True)

# validate again (must pass now) and save artifact
artifact = ln.Artifact.from_spatialdata(
    spatialdata, key="examples/spatialdata1.zarr", schema=sdata_schema
).save()
artifact.describe()
!python scripts/curate_spatialdata.py
Hide code cell output
 connected lamindb: testuser1/test-curate
/opt/hostedtoolcache/Python/3.10.18/x64/lib/python3.10/site-packages/spatialdata/models/models.py:1144: UserWarning: Converting `region_key: region` to categorical dtype.
  return convert_region_column_to_categorical(adata)
! 1 term not validated in feature 'columns' in slot 'attrs': 'random_int'
    → fix typos, remove non-existent values, or save terms via: curator.slots['attrs'].cat.add_new_from('columns')
! 2 terms not validated in feature 'columns' in slot 'tables:table:obs': 'instance_id', 'region'
    → fix typos, remove non-existent values, or save terms via: curator.slots['tables:table:obs'].cat.add_new_from('columns')
! 1 term not validated in feature 'columns' in slot 'tables:table:var.T': 'ENSG00000999999'
    → fix typos, remove non-existent values, or save terms via: curator.slots['tables:table:var.T'].cat.add_new_from('columns')
! no run & transform got linked, call `ln.track()` & re-run
INFO     The Zarr backing store has been changed from None the new file path:   
         /home/runner/.cache/lamindb/tgb6u7IAJMzq0VBH0000.zarr                  
! 1 term not validated in feature 'columns' in slot 'attrs': 'random_int'
    → fix typos, remove non-existent values, or save terms via: curator.slots['attrs'].cat.add_new_from('columns')
! 2 terms not validated in feature 'columns' in slot 'tables:table:obs': 'instance_id', 'region'
    → fix typos, remove non-existent values, or save terms via: curator.slots['tables:table:obs'].cat.add_new_from('columns')
 returning existing schema with same hash: Schema(uid='DNfFZus0Y8MKPeeB', n=2, is_type=False, itype='Feature', hash='GRiyF-ngpfy-LuXOEdADxQ', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:47 UTC)
 returning existing schema with same hash: Schema(uid='ZSdRHkAzLmIwu99P', n=1, is_type=False, itype='Feature', hash='wHR-dlu2_qkFT25Z9EzOyg', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:47 UTC)
 returning existing schema with same hash: Schema(uid='QcUETmzb5So28uWc', n=2, is_type=False, itype='Feature', hash='wS16BpnBbAUsHr0nWXSXtg', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:47 UTC)
 returning existing schema with same hash: Schema(uid='srwCYxg1pjFNJVXq', n=1, is_type=False, itype='Feature', hash='Ine7EVp8I3R7GMje5PNUmg', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:47 UTC)
Artifact .zarr · SpatialData · dataset
├── General
│   ├── key: examples/spatialdata1.zarr
│   ├── uid: tgb6u7IAJMzq0VBH0000          hash: gYqo5qRQDBFR_II6ytmlmQ
│   ├── size: 11.6 MB                      transform: None
│   ├── space: all                         branch: all
│   ├── created_by: testuser1              created_at: 2025-07-21 11:34:04
│   ├── n_files: 113
│   └── storage path: 
/home/runner/work/lamindb/lamindb/docs/test-curate/examples/spatialdata1
.zarr
├── Dataset features
│   ├── attrs:bio2       [Feature]                                           
│   │   developmental_sta…  cat[bionty.Developmen…  adult stage                 
│   │   disease             cat[bionty.Disease]     Alzheimer disease           
│   ├── attrs:tech1      [Feature]                                           
│   │   assay               cat[bionty.Experiment…  Visium Spatial Gene Express…
│   ├── attrs2           [Feature]                                           
│   │   bio                 dict                                                
│   │   tech                dict                                                
│   ├── tables:table:obs  [Feature]                                           
│   │   sample_region       str                                                 
│   └── tables:table:var.…  [bionty.Gene.ensembl_…                              
BRCA2               num                                                 
BRAF                num                                                 
└── Labels
    └── .diseases           bionty.Disease          Alzheimer disease           
        .experimental_fac…  bionty.ExperimentalFa…  Visium Spatial Gene Express…
        .developmental_st…  bionty.DevelopmentalS…  adult stage                 

TiledbsomaExperiment

curate_soma_experiment.py
import lamindb as ln
import bionty as bt
import tiledbsoma as soma
import tiledbsoma.io

adata = ln.core.datasets.mini_immuno.get_dataset1(otype="AnnData")
tiledbsoma.io.from_anndata("small_dataset.tiledbsoma", adata, measurement_name="RNA")

obs_schema = ln.Schema(
    name="soma_obs_schema",
    features=[
        ln.Feature(name="cell_type_by_expert", dtype=bt.CellType).save(),
        ln.Feature(name="cell_type_by_model", dtype=bt.CellType).save(),
    ],
).save()

var_schema = ln.Schema(
    name="soma_var_schema",
    features=[
        ln.Feature(name="var_id", dtype=bt.Gene.ensembl_gene_id).save(),
    ],
    coerce_dtype=True,
).save()

soma_schema = ln.Schema(
    name="soma_experiment_schema",
    otype="tiledbsoma",
    slots={
        "obs": obs_schema,
        "ms:RNA.T": var_schema,
    },
).save()

with soma.Experiment.open("small_dataset.tiledbsoma") as experiment:
    curator = ln.curators.TiledbsomaExperimentCurator(experiment, soma_schema)
    curator.validate()
    artifact = curator.save_artifact(
        key="examples/soma_experiment.tiledbsoma",
        description="SOMA experiment with schema validation",
    )
assert artifact.schema == soma_schema
artifact.describe()
!python scripts/curate_soma_experiment.py
Hide code cell output
 connected lamindb: testuser1/test-curate
 returning existing Feature record with same name: 'cell_type_by_expert'
 returning existing Feature record with same name: 'cell_type_by_model'
! 1 term not validated in feature 'columns': 'sample_note'
    → fix typos, remove non-existent values, or save terms via: curator.cat.add_new_from('columns')
! no run & transform got linked, call `ln.track()` & re-run
 returning existing schema with same hash: Schema(uid='45LX4dSpkPD2DgnO', n=7, is_type=False, itype='Feature', hash='cz3FabHcc9Hn61GejKrL8Q', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:33:27 UTC)
 returning existing schema with same hash: Schema(uid='bNwlZSL5WIk0MUVr', name='soma_var_schema', n=1, is_type=False, itype='Feature', hash='8uyyWn673HEhVy6yUjW66g', minimal_set=True, ordered_set=False, maximal_set=False, branch_id=1, space_id=1, created_by_id=1, created_at=2025-07-21 11:34:09 UTC)
Artifact .tiledbsoma · tiledbsoma · dataset
├── General
│   ├── key: examples/soma_experiment.tiledbsoma
│   ├── description: SOMA experiment with schema validation
│   ├── uid: XEBevknS4Pt0CtXs0000          hash: f4gChdQ0OiSy-67w_7ULuA
│   ├── size: 23.9 KB                      transform: None
│   ├── space: all                         branch: all
│   ├── created_by: testuser1              created_at: 2025-07-21 11:34:10
│   ├── n_files: 68                        n_observations: 3
│   └── storage path: 
/home/runner/work/lamindb/lamindb/docs/test-curate/examples/soma_experim
ent.tiledbsoma
├── Dataset features
│   ├── obs7             [Feature]                                           
│   │   cell_type_by_expe…  cat[bionty.CellType]    B cell, CD8-positive, alpha…
│   │   cell_type_by_model  cat[bionty.CellType]    B cell, T cell              
│   │   perturbation        cat[ULabel[Perturbati…                              
│   │   assay_oid           cat[bionty.Experiment…                              
│   │   concentration       str                                                 
│   │   treatment_time_h    num               
                                  
│   │   donor               str                                                 
│   └── ms:RNA.T1        [Feature]                                           
var_id              cat[bionty.Gene.ensem…  CD14, CD4, CD8A             
└── Labels
    └── .genes              bionty.Gene             CD8A, CD4, CD14             
        .cell_types         bionty.CellType         B cell, T cell, CD8-positiv…

Other data structures

If you have other data structures, read: How do I validate & annotate arbitrary data structures?.

Hide code cell content
!rm -rf ./test-curate
!rm -rf ./small_dataset.tiledbsoma
!lamin delete --force test-curate
 deleting instance testuser1/test-curate