SELECT on BLOB or CLOB columns no longer requires raw byte interpretation.
The 72-byte server-side locator is wrapped in a typed BlobLocator or
ClobLocator (frozen dataclass) so the column is recognizable as
"server-side reference, not actual bytes".
Wire-protocol findings:
* Smart-LOB columns DON'T appear with their nominal type codes (102/101)
in SQ_DESCRIBE. They surface as UDTFIXED (41) with extended_id 10
(BLOB) or 11 (CLOB) and encoded_length=72 (locator size).
* Retrieving the actual bytes requires SQ_FPROUTINE (103) RPC to
invoke ifx_lo_open, plus SQ_LODATA (97) for chunked transfer, plus
another SQ_FPROUTINE for ifx_lo_close. That's a Phase 10 lift —
roughly 2x the protocol surface of Phase 8.
Server config needed (added to Phase 7 setup):
* sbspace: onspaces -c -S sbspace1 ...
* default sbspace: onmode -wm SBSPACENAME=sbspace1
What ships in Phase 9:
* informix_db.BlobLocator(raw: bytes) — 72-byte frozen wrapper
* informix_db.ClobLocator(raw: bytes) — distinct type, same shape
* Row decoder branch in _resultset.parse_tuple_payload
* Wire constants SQ_LODATA=97, SQ_FPROUTINE=103, SQ_FPARAM=104
Tests:
* 11 unit tests in test_blob_locator_unit.py (no Informix needed) —
construction, immutability, equality, hash, repr safety, size
validation.
* 4 integration tests in test_smart_lob.py — fixture seeds via JDBC
reference client (smart-LOB writes also need deferred protocols).
* RefBlob.java helper in tests/reference/ for seeding via JDBC.
Total: 64 unit + 111 integration = 175 tests.
Locator design note: __repr__ omits the raw bytes (they're opaque to
the client). Same-bytes locators of different families compare
unequal — BlobLocator(x) != ClobLocator(x) — to avoid silent type
confusion.
