select a.*,count(distinct b.id) as 'topicNum',count(distinct c.id) as 'groupNum' from resource_instance_rocketmq a left join resource_rocketmq_topic b on a.instance_id = b.instance_id left join resource_rocketmq_group c on a.instance_id = c.instance_id where a.instance_name like '%gaotu%' group by a.instance_id order by topicNum asc limit 3 offset 2

以下是将该 SQL 查询语句转换为 Golang 代码的示例：

package main

import (
	"context"
	"database/sql"
	"fmt"

	_ "github.com/go-sql-driver/mysql"
)

func main() {
	db, err := sql.Open("mysql", "user:password@tcp(host:port)/database")
	if err != nil {
		panic(err.Error())
	}
	defer db.Close()

	query := `
		SELECT a.*, COUNT(DISTINCT b.id) AS topicNum, COUNT(DISTINCT c.id) AS groupNum
		FROM resource_instance_rocketmq a
		LEFT JOIN resource_rocketmq_topic b ON a.instance_id = b.instance_id
		LEFT JOIN resource_rocketmq_group c ON a.instance_id = c.instance_id
		WHERE a.instance_name LIKE ?
		GROUP BY a.instance_id
		ORDER BY topicNum ASC
		LIMIT 3 OFFSET 2
	`
	rows, err := db.QueryContext(context.Background(), query, "%gaotu%")
	if err != nil {
		panic(err.Error())
	}
	defer rows.Close()

	for rows.Next() {
		// 读取查询结果，并进行处理
	}
}

请将代码中的 `user`、`password`、`host`、`port`、`database` 分别替换为您的 MySQL 数据库的实际连接信息。同时，您需要安装 `go-sql-driver/mysql` 包以便 Golang 代码连接 MySQL 数据库。请注意，为了防止 SQL 注入攻击，我们使用了 `?` 占位符，并将查询条件 `"gaotu"` 作为参数传入 `QueryContext` 方法中。