Files
padelnomics/transform/sqlmesh_padelnomics/README.md
Deeman ebba46f700 refactor: align transform layer with template methodology
Three deviations from the quart_saas_boilerplate methodology corrected:

1. Fix dim_cities LIKE join (data quality bug)
   - Old: FROM eurostat_cities LEFT JOIN venue_counts LIKE '%country_code%'
     → cartesian product (2.6M rows vs ~5500 expected)
   - New: FROM venue_cities (dim_venues) as primary table, Eurostat for
     enrichment only. grain (country_code, city_slug).
   - Also fixes REGEXP_REPLACE to LOWER() before regex so uppercase city
     names aren't stripped to '-'

2. Rename fct_venue_capacity → dim_venue_capacity
   - Static venue attributes with no time key are a dimension, not a fact
   - No SQL logic changes; update fct_daily_availability reference

3. Add fct_availability_slot at event grain
   - New: grain (snapshot_date, tenant_id, resource_id, slot_start_time)
   - Recheck dedup logic moves here from fct_daily_availability
   - fct_daily_availability now reads fct_availability_slot (cleaner DAG)

Downstream fixes:
- city_market_profile, planner_defaults grain → (country_code, city_slug)
- pseo_city_costs_de, pseo_city_pricing add city_key composite natural key
  (country_slug || '-' || city_slug) to avoid URL collisions across countries
- planner_defaults join in pseo_city_costs_de uses both country_code + city_slug
- Templates updated: natural_key city_slug → city_key

Added transform/sqlmesh_padelnomics/CLAUDE.md documenting data modeling rules,
conformed dimension map, and source integration architecture.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-02-23 21:17:04 +01:00

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4.5 KiB
Markdown

# Padelnomics Transform (SQLMesh)
3-layer SQL transformation pipeline using SQLMesh + DuckDB. Reads from the landing zone, produces analytics-ready tables consumed by the web app via an atomically-swapped serving DB.
## Running
```bash
# From repo root — plan all changes (shows what will run)
uv run sqlmesh -p transform/sqlmesh_padelnomics plan
# Apply to production
uv run sqlmesh -p transform/sqlmesh_padelnomics plan prod
# Run model tests
uv run sqlmesh -p transform/sqlmesh_padelnomics test
# Format SQL
uv run sqlmesh -p transform/sqlmesh_padelnomics format
# Export serving tables to analytics.duckdb (run after SQLMesh)
DUCKDB_PATH=data/lakehouse.duckdb SERVING_DUCKDB_PATH=data/analytics.duckdb \
uv run python -m padelnomics.export_serving
```
## 3-layer architecture
```
landing/ ← raw files (extraction output)
├── overpass/*/*/courts.json.gz
├── eurostat/*/*/urb_cpop1.json.gz
└── playtomic/*/*/tenants.json.gz
staging/ ← reads landing files directly, type casting, dedup
├── staging.stg_padel_courts
├── staging.stg_playtomic_venues
└── staging.stg_population
foundation/ ← business logic, dimensions, facts
├── foundation.dim_venues ← conformed venue dimension (Playtomic + OSM)
├── foundation.dim_cities ← conformed city dimension (venue-derived + Eurostat)
├── foundation.dim_venue_capacity ← static capacity attributes per venue
├── foundation.fct_availability_slot ← event-grain: one row per deduplicated slot
└── foundation.fct_daily_availability← venue-day aggregate: occupancy + revenue estimates
serving/ ← pre-aggregated for web app
├── serving.city_market_profile
└── serving.planner_defaults
```
### staging/ — read landing files + type casting
- Reads landing zone JSON files directly with `read_json(..., format='auto', filename=true)`
- Uses `@LANDING_DIR` variable for file path discovery
- Casts all columns to correct types: `TRY_CAST(... AS DOUBLE)`
- Deduplicates where source produces duplicates (ROW_NUMBER partitioned on ID)
- Validates coordinates, nulls, and data quality inline
- Naming: `staging.stg_<source>`
### foundation/ — business logic
- Dimensions (`dim_*`): slowly changing attributes, one row per entity
- Facts (`fact_*`): events and measurements, one row per event
- May join across multiple staging models from different sources
- Naming: `foundation.dim_<entity>`, `foundation.fact_<event>`
### serving/ — analytics-ready aggregates
- Pre-aggregated for specific web app query patterns
- These are the only tables the web app reads (via `analytics.duckdb`)
- Queried from `analytics.py` via `fetch_analytics()`
- Naming: `serving.<purpose>`
## Two-DuckDB architecture
```
data/lakehouse.duckdb ← SQLMesh exclusive write (DUCKDB_PATH)
├── staging.*
├── foundation.*
└── serving.*
data/analytics.duckdb ← web app read-only (SERVING_DUCKDB_PATH)
└── serving.* ← atomically replaced by export_serving.py
```
SQLMesh holds an exclusive write lock on `lakehouse.duckdb` during plan/run.
The web app needs read-only access at all times. `export_serving.py` copies
`serving.*` tables to a temp file, then atomically renames it to `analytics.duckdb`.
The web app detects the inode change on next query — no restart needed.
**Never point DUCKDB_PATH and SERVING_DUCKDB_PATH to the same file.**
## Adding a new data source
1. Add an extractor in `extract/padelnomics_extract/` (see extraction README)
2. Add a staging model: `models/staging/stg_<source>.sql` that reads landing files directly
3. Join into foundation or serving models as needed
## Model materialization
| Layer | Default kind | Rationale |
|-------|-------------|-----------|
| staging | FULL | Re-reads all landing files; cheap with DuckDB parallel scan |
| foundation | FULL | Business logic rarely changes; recompute is fast |
| serving | FULL | Small aggregates; web app needs latest at all times |
For large historical tables, switch to `kind INCREMENTAL_BY_TIME_RANGE` with a time partition column.
## Environment variables
| Variable | Default | Description |
|----------|---------|-------------|
| `LANDING_DIR` | `data/landing` | Root of the landing zone |
| `DUCKDB_PATH` | `data/lakehouse.duckdb` | DuckDB file (SQLMesh exclusive write access) |
| `SERVING_DUCKDB_PATH` | `data/analytics.duckdb` | Serving DB (web app reads from here) |