entc/gen/template: remove irrelevant code from templates (#481)

examples/start/ent/ent.go

@@ -7,7 +7,6 @@
 package ent
 
 import (
-	"context"
 	"errors"
 	"fmt"
 	"strings"
@@ -224,44 +223,3 @@ func rollback(tx dialect.Tx, err error) error {
 	}
 	return err
 }
-
-// insertLastID invokes the insert query on the transaction and returns the LastInsertID.
-func insertLastID(ctx context.Context, tx dialect.Tx, insert *sql.InsertBuilder) (int64, error) {
-	query, args := insert.Query()
-	// PostgreSQL does not support the LastInsertId() method of sql.Result
-	// on Exec, and should be extracted manually using the `RETURNING` clause.
-	if insert.Dialect() == dialect.Postgres {
-		rows := &sql.Rows{}
-		if err := tx.Query(ctx, query, args, rows); err != nil {
-			return 0, err
-		}
-		defer rows.Close()
-		if !rows.Next() {
-			return 0, fmt.Errorf("no rows found for query: %v", query)
-		}
-		var id int64
-		if err := rows.Scan(&id); err != nil {
-			return 0, err
-		}
-		return id, nil
-	}
-	// MySQL, SQLite, etc.
-	var res sql.Result
-	if err := tx.Exec(ctx, query, args, &res); err != nil {
-		return 0, err
-	}
-	id, err := res.LastInsertId()
-	if err != nil {
-		return 0, err
-	}
-	return id, nil
-}
-
-// keys returns the keys/ids from the edge map.
-func keys(m map[int]struct{}) []int {
-	s := make([]int, 0, len(m))
-	for id := range m {
-		s = append(s, id)
-	}
-	return s
-}