Golang - 为什么 SQL 占位符不起作用？

Question

我的代码如下（我使用 gorm）：

e.GET("/search", func(c echo.Context) error {
    keyword := c.QueryParam("keyword")

    results := make([]searchResult, 0)
    if keyword != "" {
        db, err := models.ConnectDB()
        defer db.Close()
        if err != nil {
            return err
        }

        rows, err := db.Raw("SELECT songs.name, singers.name, albums.name FROM songs, singers, albums WHERE (songs.singer_id = singers.id AND songs.album_id = albums.id) AND (songs.name LIKE '%?%' OR singers.name LIKE '%?%' OR albums.name LIKE '%?%')", keyword, keyword, keyword).Rows()
        defer rows.Close()

        var songName, singerName, albumName string
        if err == nil {
            for rows.Next() {
                rows.Scan(&songName, &singerName, &albumName)
                results = append(results, searchResult{
                    SongName:   songName,
                    SingerName: singerName,
                    AlbumName:  albumName,
                })
            }
        } else {
            return err
        }
    }
    return c.Render(http.StatusOK, "search", results)
})

我收到错误：sql: statement expects 0 inputs; got 3，所以这意味着未解析占位符。谁能给我一些想法？

我无法自己找出原因。

请帮我。谢谢。

Answer 1

您不能将占位符放在像'?'.

它不像字符串插值那样工作，它只是变量绑定。

所以尝试：

    searchKeyword := "%" + keyword + "%"
    rows, err := db.Raw(`SELECT songs.name, singers.name, albums.name 
      FROM songs, singers, albums 
      WHERE (songs.singer_id = singers.id AND songs.album_id = albums.id) 
      AND (songs.name LIKE ? OR singers.name LIKE ? OR albums.name LIKE ?)`, 
      searchKeyword, 
      searchKeyword, 
      searchKeyword).Rows()