Change the Player entity schema or the seed dataset, add EF Core migrations for both SQLite and PostgreSQL, keep test fakes in sync, and switch the active database provider (DATABASE_PROVIDER/DATABASE_URL/STORAGE_PATH). Use when changing entity fields, seed players, or migrations.
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---
name: change-data
description: Change the Player entity schema or the seed dataset, add EF Core migrations for both SQLite and PostgreSQL, keep test fakes in sync, and switch the active database provider (DATABASE_PROVIDER/DATABASE_URL/STORAGE_PATH). Use when changing entity fields, seed players, or migrations.
---
# Change data
Schema changes are on the "ask before changing" list: confirm with the user and
make sure an issue exists first. Never rename the migration namespace constants
in `Migrations/ProviderSpecificMigrationsAssembly.cs`.
Source paths below are relative to `src/Dotnet.Samples.AspNetCore.WebApi/`.
Test paths start with `test/`. Repository-root files (`README.md`,
`CLAUDE.md`, `docs/`) use repository-root paths.
## Schema change
1. Update the `Player` entity in `Models/Player.cs`, then the DTOs and
`Mappings/PlayerMappingProfile.cs`.
2. Update the entity configuration in `Data/PlayerDbContext.cs` if needed.
3. Add one migration per provider (same name for both), running from the
repository root:
```bash
# SQLite (default)
dotnet ef migrations add <Name> --project src/Dotnet.Samples.AspNetCore.WebApi
# PostgreSQL
DATABASE_PROVIDER=postgres DATABASE_URL="Host=localhost;..." \
dotnet ef migrations add <Name> --project src/Dotnet.Samples.AspNetCore.WebApi --output-dir Migrations/Npgsql
```
4. Review both generated migrations; do not edit migrations that are already
merged.
## Seed data change
1. Update `Utilities/PlayerData.cs` — it is the single source of truth for
`HasData()` in `PlayerDbContext` and for `PlayerFakes` in tests.
2. Add a data migration for both providers (as above) so existing databases
get the change; `MigrateAsync()` applies it at startup.
3. Check `test/.../Utilities/PlayerFakes.cs` and any test that asserts on
specific players (squad numbers, counts).
## Switch database provider
- `DATABASE_PROVIDER=postgres` selects PostgreSQL; unset (or `sqlite`) keeps
SQLite.
- `DATABASE_URL` (required for PostgreSQL) uses the Npgsql format:
`Host=...;Database=...;Username=...;Password=...`.
- `STORAGE_PATH` overrides the SQLite file path (default
`AppContext.BaseDirectory/storage/players-sqlite3.db`).
- `ProviderSpecificMigrationsAssembly` loads only the active provider's
migrations; no code change is needed to switch.
## Finish
Run `dotnet test --settings .runsettings`, update the Database section of
`README.md` if behavior changed, then run `/pre-commit`.
