Drop RowsAffected check from Delete methods

Deletes are idempotent — zero affected rows is not an error.

Signed-off-by: Émile Ré <emile@probo.com>

contrib/claude/coredata.md

@@ -113,6 +113,8 @@ This ensures the compiler catches renamed or removed enum values instead of sile
 
 Use `conn.Query` + `pgx.Collect*` only for `SELECT` and `INSERT … RETURNING` statements that return rows. For `UPDATE` and `DELETE`, use `conn.Exec` — there is no need for `RETURNING` since the caller already owns all the field values.
 
+**Delete must not check `RowsAffected()`.** A DELETE that affects zero rows is not an error — the resource may have already been deleted (idempotent deletes). Only `Update` checks `RowsAffected() == 0` to return `ErrResourceNotFound`.
+
 ```go
 // Single row (SELECT / INSERT … RETURNING)
 rows, err := conn.Query(ctx, q, args)
@@ -127,7 +129,7 @@ rows, err := conn.Query(ctx, q, args)
 assets, err := pgx.CollectRows(rows, pgx.RowToAddrOfStructByName[Asset])
 *a = assets
 
-// Update / Delete — no RETURNING
+// Update — no RETURNING, check RowsAffected
 result, err := conn.Exec(ctx, q, args)
 if err != nil {
     return err
@@ -135,6 +137,12 @@ if err != nil {
 if result.RowsAffected() == 0 {
     return ErrResourceNotFound
 }
+
+// Delete — no RETURNING, do NOT check RowsAffected
+_, err := conn.Exec(ctx, q, args)
+if err != nil {
+    return err
+}
 ```
 
 ## Sentinel errors

pkg/coredata/common_third_party.go

@@ -429,15 +429,11 @@ func (t CommonThirdParty) Delete(
 
 	args := pgx.StrictNamedArgs{"id": id}
 
-	result, err := conn.Exec(ctx, q, args)
+	_, err := conn.Exec(ctx, q, args)
 	if err != nil {
 		return fmt.Errorf("cannot delete common third party: %w", err)
 	}
 
-	if result.RowsAffected() == 0 {
-		return ErrResourceNotFound
-	}
-
 	return nil
 }
 

pkg/coredata/common_third_party_domain.go

@@ -172,15 +172,11 @@ func (d CommonThirdPartyDomain) Delete(
 
 	args := pgx.StrictNamedArgs{"id": d.ID}
 
-	result, err := conn.Exec(ctx, q, args)
+	_, err := conn.Exec(ctx, q, args)
 	if err != nil {
 		return fmt.Errorf("cannot delete common third party domain: %w", err)
 	}
 
-	if result.RowsAffected() == 0 {
-		return ErrResourceNotFound
-	}
-
 	return nil
 }
 

pkg/coredata/common_tracker_pattern.go

@@ -274,15 +274,11 @@ func (p CommonTrackerPattern) Delete(
 
 	args := pgx.StrictNamedArgs{"id": id}
 
-	result, err := conn.Exec(ctx, q, args)
+	_, err := conn.Exec(ctx, q, args)
 	if err != nil {
 		return fmt.Errorf("cannot delete common tracker pattern: %w", err)
 	}
 
-	if result.RowsAffected() == 0 {
-		return ErrResourceNotFound
-	}
-
 	return nil
 }