# sqlalchemy.exc.NoSuchModuleError: Can't load plugin: sqlalchemy.dialects:postgresql

- **ID:** `python/sqlalchemy-no-engine-found`
- **Domain:** python
- **Category:** config_error
- **Verification:** ai_generated
- **Fix Rate:** 80%

## Root Cause

Missing or misconfigured database driver (e.g., psycopg2 not installed).

## Version Compatibility

| Version | Status | Introduced | Deprecated |
|---------|--------|------------|------------|
| 3.x | active | — | — |

## Workarounds

1. **Install the correct driver.** (95% success)
   ```
   pip install psycopg2-binary
   ```
2. **Use correct connection string format.** (90% success)
   ```
   engine = create_engine('postgresql://user:pass@localhost/dbname')
   ```

## Dead Ends

- **Installing wrong package like 'postgresql' instead of 'psycopg2-binary'.** — SQLAlchemy requires specific driver packages; generic packages don't work. (70% fail)
- **Setting incorrect dialect string like 'postgres' instead of 'postgresql'.** — Dialect names are case-sensitive and must match exactly. (80% fail)