tdfs4ds.utils.storage¶

tdfs4ds.utils.storage ¶

Backing-table storage selection for TimeManager / FilterManager.

On Vantage Cloud Lake (VCL), a tdstone2 model run via the Apply backend scores on the Analytical Compute Cluster (ACC), which reads its dataset from the Object File System (OFS). Passing storage='OFS' to a manager constructor makes that manager's hidden table be created on OFS (MAP = TD_MAP2, STORAGE = TD_OFSSTORAGE) instead of the default block storage. The choice is per manager (a constructor argument, never a global) so block-storage (full primary cluster) processes and OFS/Apply processes can coexist in the same session.

Making an Apply-scored view that references a manager work on the ACC needs TWO things (confirmed live on VCL):

The manager table on OFS — storage='OFS' here, so the ACC can read it. A block-storage manager table read by an ACC query raises Error 6881 ("Query is not eligible to run on Analytical Compute Cluster").
The filter referenced as a JOIN, not a correlated scalar subquery. The ACC rejects ... WHERE d <= (SELECT BUSINESS_DATE FROM <tm_view>) with 6881, but accepts a JOIN to the manager view. Authoring the filter as a JOIN is the user's responsibility — it is a property of the scoring/feature view's SQL, not of the manager. (A hard-coded literal also passes, but a JOIN keeps the reference dynamic so time-travel via update() still works.)

So storage='OFS' is necessary but not sufficient on its own: OFS + JOIN scores; OFS + scalar subquery still 6881s. For a view that reads an OFS table directly (no subquery), storage='OFS' is all that's needed.

Backward compatibility: the default (storage=None) emits no storage clause at all — byte-identical DDL to previous versions.

_OFS_ALIASES `module-attribute` ¶

_OFS_ALIASES = {'OFS', 'TD_OFSSTORAGE', 'LAKE', 'OBJECT'}

_DEFAULT_ALIASES `module-attribute` ¶

_DEFAULT_ALIASES = {'', 'DEFAULT', 'BLOCK', 'PRIMARY', 'TD_MAP1'}

DEFAULT_OFS_MAP `module-attribute` ¶

DEFAULT_OFS_MAP = 'TD_MAP2'

ACC_6881_HINT `module-attribute` ¶

ACC_6881_HINT = "Error 6881 (not eligible for the Analytical Compute Cluster): for a tdstone2-Apply view that references a TimeManager/FilterManager, TWO things are needed — (a) the manager table on OFS (storage='OFS'), so the ACC can read it, AND (b) the filter written as a JOIN to the manager view, NOT a correlated scalar subquery '(SELECT BUSINESS_DATE FROM <view>)', which the ACC rejects. OFS + JOIN scores; OFS + scalar subquery still 6881s. The filter shape is the user's responsibility. Also: run the model's score() BEFORE upload_features — roll_out/run() cannot drive an Apply model (its ingestion CTAS also hits 6881)."

resolve_storage ¶

resolve_storage(storage)

Normalize a storage selector to 'OFS' or None (system default).

Parameters:

Name	Type	Description	Default
`storage`		`None`/`'OFS'`/`'default'`/`'block'`/... (case-insensitive).	required

Returns:

Type	Description
	`'OFS'` for an OFS selector, else `None` (system default / block storage).
	Unknown values fall back to `None` (backward-safe) with a warning.

storage_clause ¶

storage_clause(storage, ofs_map=DEFAULT_OFS_MAP)

Return the CREATE TABLE options fragment for the requested storage.

The fragment is inserted immediately after the table name, e.g.::

CREATE TABLE db.tbl{storage_clause(...)} ( ... ) PRIMARY INDEX (...)

Parameters:

Name	Type	Description	Default
`storage`		storage selector (see :func:`resolve_storage`).	required
`ofs_map`		the map paired with `STORAGE = TD_OFSSTORAGE` when OFS is requested.	`DEFAULT_OFS_MAP`

Returns:

Type	Description
	`''` for the system default (unchanged DDL), or
	`',\n MAP = <ofs_map>,\n STORAGE = TD_OFSSTORAGE'` for OFS.

is_acc_ineligible_error ¶

is_acc_ineligible_error(exc)

True if exc looks like a Teradata ACC-ineligibility error (6881).

tdfs4ds.utils.storage¶