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SQLBlobBackend

API reference for SQLBlobBackend — stores files as key-value rows in any SQLAlchemy-supported SQL database.

SQLBlobBackend 

SQLBlobBackend(
    url: str | None = None,
    *,
    engine: Engine | None = None,
    table_name: str = "remote_store_objects",
    create_table: bool = True,
    max_blob_size: int | None = None,
    reject_write_under_file_ancestor: bool = False,
)

SQL key-value blob store implementing the full Backend contract.

Uses a SQL table as key-value storage. Each row holds one "file" with its key, data, and metadata. SQLite receives WAL mode and PRAGMA tuning automatically.

Supports all capabilities except LAZY_READ.

Note

Non-lazy reads and writes. Both read() and write() materialize the full content in memory. read() loads the entire BLOB before returning a stream (no LAZY_READ). write() reads the full stream before issuing the SQL INSERT/UPDATE because BLOB columns require complete data in a single statement. For files larger than process memory, use a blob-storage backend (S3, Local, Azure) instead.

Parameters:

  • reject_write_under_file_ancestor (bool, default: False ) –

    If True, write / write_atomic / open_atomic / move / copy issue one SELECT 1 per slash-aligned ancestor of the target path and raise InvalidPath on the first regular-file hit, matching the cross-backend contract that hierarchical filesystems enforce natively. Default False; paths without slashes short-circuit.

resolve 

resolve(path: str) -> ResolutionPlan

Return a ResolutionPlan with SQL blob details.

Parameters:

  • path (str) –

    Backend-relative key.

Returns:

See also