我想制作一个 function 从某些列获取数据

Question

i've created the code, but its not completed.Could anyone help me to complete the code? or how the complete code looks like.Language im using is Go and the database is PostgreSQL

func (m *rg) GetAllRegional(filter map[string]interface{}) ([]*model.Regional, int64, error) {
    query := `SELECT
        title,
        language,
        isviewmain
        FROM Regional`

    stmt, err := m.DB.Prepare(query)
    if err != nil {
        log.Println(err)
        return nil, err
    }

    return nil, -1, nil
}

Answer 1

here's a link to a previous answer: (GoLANG) *sql.DB Scan rows into string array pointer

Edit: Here's an example that's a more similar to your example.

This is for mariaDB btw, make sure to change the connection string and sql.Open to postgreSQL

type rg struct {
    DB *sql.DB
}

func init() {
    // fill it with your info
    db, err := connect("testDB" /* DB */, "testUser" /* DbUser */, "testPass" /* DbPw */)
    if err != nil {
        log.Fatal(err)
    }

    filter := map[string]interface{}{}
    r, i, err := db.GetAllRegional(filter)
    if err != nil {
        log.Fatal(err)
    }

    log.Printf("r: %+v\ni: %+v\n", r, i)
}

// connect returns a rg
func connect(dbName, username, password string) (rg, error) {
    cs := username + ":" + password + "@tcp(" + "YourDbHost" + ":3306)/" + dbName

    db, err := sql.Open("mysql", cs)
    if err != nil {
        log.Println(err.Error())
        return rg{}, err
    }
    return rg{db}, nil
}

// GetAllRegional ...
func (m *rg) GetAllRegional(filter map[string]interface{}) ([]string, int64, error) {
    // checking if the connection is alive
    err := m.DB.Ping()
    if err != nil {
        log.Fatal(err)
        return nil, 0, err
    }

    q := `SELECT title, language, isviewmain FROM Regional`
    rows, err := m.DB.Query(q)
    if err != nil {
        log.Fatal(err)
        return nil, 0, err
    }
    defer rows.Close()

    // Not sure what you're returning on the model
    // returning a slice instead
    var regional []string
    for rows.Next() {
        var temp string

        err = rows.Scan(&temp)
        if err != nil {
            log.Println(err.Error())
            if err == sql.ErrNoRows {
                log.Println(sql.ErrNoRows.Error())
            }
            return nil, 0, err
        }

        regional = append(regional, temp)
    }

    return regional, 1, nil
}