Drop fact_interventions (440K rows), mv_patient_treatment_summary (35K rows),
ref_drug_snomed_mapping (144K rows), and processed_files — all unused since
the app moved to pre-computed pathway_nodes.
Key changes:
- Rewrite load_data() to source from pathway_nodes + pathway_refresh_log
- Remove 7 dead methods and 8 dead state vars from pathways_app.py
- Delete patient_data.py, load_snomed_mapping.py, test_large_dataset_performance.py
- Remove SQLiteDataLoader (depended on fact_interventions)
- Remove file tracking schema (processed_files tracked fact_interventions loads)
- Remove legacy diagnosis functions from diagnosis_lookup.py
- Add source_row_count migration for pathway_refresh_log
- Clean all cross-references in __init__.py, data_source.py, migrate.py
- Add chart_type column (TEXT NOT NULL DEFAULT 'directory')
- Update UNIQUE constraint to (date_filter_id, chart_type, ids)
- Add idx_pathway_nodes_chart_type index for filtering
- Add migrate_pathway_nodes_chart_type() function for existing databases
- Update initialize_database() to run migration automatically
- Existing rows default to 'directory' chart type
- Add REF_DRUG_SNOMED_MAPPING_SCHEMA with 11 columns for direct SNOMED mapping
- Add 5 indexes for lookup performance (drug, cleaned_drug, snomed, search_term, composite)
- Add create_drug_snomed_mapping_table() helper function
- Update helper functions (drop, get_counts, verify_exists) to include new table
- Table is included in REFERENCE_TABLES_SCHEMA and created by migration
Add three new tables to support pre-computed pathway data:
- pathway_date_filters: 6 pre-defined date filter combinations
- pathway_nodes: pre-computed pathway hierarchy with all visualization data
- pathway_refresh_log: tracks data refresh status
Includes:
- 8 indexes for efficient filtering by date_filter_id, trust, directory, drug
- Helper functions: create/drop/verify/get_counts for pathway tables
- clear_pathway_nodes() for selective or full data clearing
- get_pathway_refresh_status() for checking last refresh
- Integration with existing ALL_TABLES_SCHEMA and combined helpers