New query functions in src/data_processing/pathway_queries.py:
- get_drug_market_share: Level 3 drug nodes grouped by directory
- get_pathway_costs: Level 4+ pathway nodes with cost_pp_pa
- get_cost_waterfall: Directorate cost per patient from level 3 aggregation
- get_drug_transitions: Sankey source/target drug transitions with ordinal line labels
- get_dosing_intervals: Parsed average_spacing by trust/directory
- get_drug_directory_matrix: Directory x drug pivot with patient/cost metrics
- get_treatment_durations: Weighted avg_days by drug within directorates
Thin wrappers added in dash_app/data/queries.py for all 7 functions.
- Add _prune_empty_ancestors() to remove directorate/trust nodes with no
matching children when drug or directorate filters are active (e.g.,
filtering by Immunoglobulin no longer shows empty Ophthalmology box)
- Sum level-3 drug nodes for KPI values when entity filters are active
instead of using the root node's pre-computed unfiltered totals
Drug filter WHERE clause used `drug_sequence IS NULL` to keep ancestor nodes,
but levels 0-2 have empty string '' not NULL. Changed to level-based gating:
- Drug filter: `(level < 3 OR drug_sequence LIKE ...)`
- Directorate filter: `(level < 2 OR directory IN (...) OR directory IS NULL OR directory = '')`
- Trust filter was already correct (had `OR trust_name = ''`)
Extract load_data() and load_pathway_data() logic from Reflex AppState
into standalone functions in src/data_processing/pathway_queries.py.
Create thin dash_app/data/queries.py wrapper with DB_PATH resolution.
Andrew Charlwood