add dlte schema docs

docs/schema.md

@@ -0,0 +1,143 @@
+# `logo-lab/dlte` per-config schema reference
+
+## `lake` config (5 splits)
+
+### `parents_tabfact`, `parents_wtq`
+
+| Column | Type | Notes |
+|---|---|---|
+| `table_id` | string | original parent identifier (TabFact: `r-N`; WTQ: csv id) |
+| `source` | string | `tabfact` or `wtq` |
+| `n_rows` | int32 | parent row count |
+| `n_cols` | int32 | parent column count |
+| `header` | list<string> | column names |
+| `table_csv` | large_string | full parent serialized as CSV |
+| `provenance_url` | string | upstream link |
+| `license_tag` | string | per-row license inheritance |
+
+### `targets`
+
+| Column | Type | Notes |
+|---|---|---|
+| `target_id` | string | unique fragment id |
+| `parent_id` | string | links to parents_*.table_id |
+| `parent_source` | string | `tabfact` or `wtq` |
+| `kind` | string | `union` or `join` |
+| `noise_tier` | string | `clean` / `schema` / `cell` / `hard` |
+| `removed_rows` | list<int32> | indices of rows removed from parent (only for `union`) |
+| `removed_cols` | list<int32> | indices of cols removed from parent (only for `join`) |
+| `table_csv` | large_string | the fragment table |
+| `license_tag` | string | inherited |
+
+### `distractors`
+
+| Column | Type | Notes |
+|---|---|---|
+| `distractor_id` | string | matches `manifests/ckan_distractor_ids` |
+| `source` | string | always `lakebench_ckan` |
+| `table_csv` | large_string | the CKAN distractor table |
+| `license_tag` | string | `cc-by-4.0 (LakeBench Zenodo); per-portal upstream` |
+
+### `queries`
+
+| Column | Type | Notes |
+|---|---|---|
+| `query_id` | string | seed query identifier |
+| `parent_id` | string | parent the query was derived from |
+| `parent_source` | string | `tabfact` or `wtq` |
+| `noise_tier` | string | |
+| `seed_csv` | large_string | the seed query (parent with rows + cols removed) |
+| `removed_rows` | list<int32> | the union target's rows |
+| `removed_cols` | list<int32> | the join target's cols |
+| `license_tag` | string | inherited |
+
+## `manifests` config (8 splits)
+
+### `splits`
+
+| Column | Type | Notes |
+|---|---|---|
+| `parent_id` | string | |
+| `split` | string | `train` / `dev` / `test` |
+| `parent_source` | string | |
+
+(827 train / 207 dev / 345 test rows)
+
+### `parents_filtered`
+
+| Column | Type | Notes |
+|---|---|---|
+| `parent_id` | string | |
+| `parent_source` | string | |
+| `n_rows` | int32 | |
+| `n_cols` | int32 | |
+| `passes_filter` | bool | should always be `true` since this is the post-filter list |
+| `provenance_url` | string | |
+
+(1,379 rows)
+
+### `fragments` (16,548 rows)
+
+| Column | Type | Notes |
+|---|---|---|
+| `fragment_id` | string | |
+| `parent_id` | string | |
+| `parent_source` | string | |
+| `kind` | string | `seed` / `union_target` / `join_target` |
+| `noise_tier` | string | |
+| `provenance` | string | JSON-encoded extra context |
+
+### `lake` (the retrieval lake of exactly 47,772 tables)
+
+This split lists only the tables that are searchable in Stage-1 retrieval —
+**i.e., union/join targets + CKAN distractors**. Parents and query seeds are
+pipeline I/O (kept in the `lake` config's other splits and the `manifests`
+config, but not in *this* split).
+
+| Column | Type | Notes |
+|---|---|---|
+| `table_id` | string | |
+| `kind` | string | `union_target` / `join_target` / `distractor` (exactly these three) |
+| `parent_id` | string | nullable; only set for derivatives |
+| `parent_source` | string | nullable; `tabfact` or `wtq` for derivative targets |
+| `noise_tier` | string | nullable; `clean` / `schema` / `cell` / `hard` for targets only |
+
+### `ckan_distractor_ids`
+
+| Column | Type | Notes |
+|---|---|---|
+| `distractor_id` | string | (36,740 rows; matches `lake.distractors.distractor_id`) |
+
+### `query_tasks`
+
+| Column | Type | Notes |
+|---|---|---|
+| `query_id` | string | |
+| `parent_id` | string | |
+| `parent_source` | string | |
+| `noise_tier` | string | |
+| `task_type` | string | one of `union_only` / `join_only` / `union_and_join` |
+| `gt_union_target_ids` | list<string> | ground-truth union target fragment ids |
+| `gt_join_target_ids` | list<string> | ground-truth join target fragment ids |
+
+### `gt_validation`
+
+Per-query validation rows used for the dev-split macro-F1 calibration of
+Stage-2 thresholds.
+
+| Column | Type | Notes |
+|---|---|---|
+| `query_id` | string | |
+| `gt_action` | string | `union` / `join` / `none` |
+| `gt_target_id` | string | nullable |
+| `metadata` | string | JSON-encoded |
+
+### `table_maps`
+
+| Column | Type | Notes |
+|---|---|---|
+| `table_id` | string | |
+| `kind` | string | |
+| `parent_id` | string | |
+| `csv_path` | string | path within `lake/*` parquet (informational only — actual csv lives in `lake` config) |
+| `stage2_calibrated_thresholds` | string | JSON-encoded; only populated for the (Stage-1 backbone, Stage-2 model) calibration result rows used in the paper |