probo / rules

---
description: Delete methods must not check RowsAffected — deletes are idempotent
globs: "pkg/coredata/**/*.go"
alwaysApply: false
---

# Delete must not check RowsAffected

In `Delete` methods, do **not** check `result.RowsAffected() == 0`. A DELETE that affects zero rows is not an error — the resource may have already been deleted. Deletes are idempotent.

Discard the result with `_`:

```go
// GOOD — Delete ignores RowsAffected
_, err := conn.Exec(ctx, q, args)
if err != nil {
	return fmt.Errorf("cannot delete foo: %w", err)
}
return nil

// BAD — Delete checks RowsAffected
result, err := conn.Exec(ctx, q, args)
if err != nil {
	return fmt.Errorf("cannot delete foo: %w", err)
}
if result.RowsAffected() == 0 {
	return ErrResourceNotFound
}
return nil
```

This rule applies only to `Delete`. `Update` methods **must** still check `RowsAffected() == 0` and return `ErrResourceNotFound`.

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