[bug] IntegrityError When Adding Texts to Vector Store with Metadata

[Ocyss]

I have written the following code based on the example documentation. However, I encountered an error when attempting to add texts to the vector store with metadata.

Code

Here is the relevant code snippet:

pg_engine_entity = PGEngine.from_engine(engine)

await pg_engine_entity.ainit_vectorstore_table(
    table_name=TABLE_NAME_ENTITY,
    vector_size=1024,
    overwrite_existing=True,
    metadata_columns=[
        Column("entity_id", "INTEGER", nullable=False)
    ],
)

vectorstore_entity = await PGVectorStore.create(
    engine=pg_engine_entity,
    table_name=TABLE_NAME_ENTITY,
    embedding_service=openai_embeddings,
)

vid = (
    await vectorstore.aadd_texts(
        [memory_flow.content],
        [
            {
                "entity_id": entity_id
            }
        ],
        [uuid.uuid4()],
    )
)[0]

Error Message

When executing the code, I received the following error:

IntegrityError: (sqlalchemy.dialects.postgresql.asyncpg.IntegrityError) <class 'asyncpg.exceptions.NotNullViolationError'>: null value in column "entity_id" of relation "VectorEntity" violates not-null constraint
DETAIL: Failing row contains (63c145e7-8663-471e-845e-d96714f651e2, 一条测试。, [-0.030918628,0.017731816,-0.03639662,-0.00945296,-0.03324449,-0..., null, null, {"entity_id": 1006}).

Expected Behavior

The text and metadata should be successfully added to the vector store without violating the not-null constraint on the entity_id column.

Actual Behavior

The operation fails with an IntegrityError due to a null value in the entity_id column, despite passing a value in the metadata.

Environment

• Library Version:
  • SQLModel: 0.0.24
  • asyncpg: 0.30.0
  • FastAPI: 0.115.12
  • LangChain: 0.3.25
  • Pydantic: 2.11.4
• Database: PostgreSQL
• Python Version: 3.13.2
• Other Relevant Info: Package manager: uv

Additional Notes

• It seems that the metadata value for entity_id is not being correctly mapped to the column in the database.
• I suspect there might be an issue with how the metadata is processed or inserted into the table.

Request for Help

Could you please help identify why the entity_id value from the metadata is not being inserted into the database column? Any guidance or fixes would be greatly appreciated!

Additional Question on SQL Construction

I also noticed that the add_embeddings method uses f-strings to manually concatenate SQL statements. Could this potentially lead to security issues, and is there a reason for not using SQLAlchemy's table objects or parameterized queries?