如何在Golang中使用命令执行SQL文件

Question

everyone, I have some troubles with postgresql in golang. I have an sql file (database.sql), and before starting my server I want to exec some command, it look's like that

CREATE TABLE forums (
  id BIGSERIAL primary key,
  slug TEXT NOT NULL UNIQUE,
  title TEXT,
  author TEXT references users(login),
  threads BIGINT DEFAULT 0,
  posts BIGINT DEFAULT 0
);

I know, that I should use db.Exec(request), but i have many requests ("CREATE TABLE user" and others...)

I have no idea, how to do that

Help, and thanks a lot!

Answer 1

You can read the file's contents into a string and pass that to Exec.

query, err := ioutil.ReadFile("path/to/database.sql")
if err != nil {
    panic(err)
}
if _, err := db.Exec(query); err != nil {
    panic(err)
}

---

If your database.sql is formated in such a way, or it contains queries that break db.Exec, then you could use os/exec together with psql (if it's installed on the machine on which the code is being run).

cmd := exec.Command("psql", "-d", "database_name", "-f", "path/to/database.sql")
stderr, err := cmd.StderrPipe()
if err != nil {
    panic(err)
}

if err := cmd.Start(); err != nil {
    panic(err)
}

errout, _ := ioutil.ReadAll(stderr)
if err := cmd.Wait(); err != nil {
    fmt.Println(errout)
    panic(err)
}