更改sqlite中列中的值

Question

我需要更新某個表中列中的值。 我試過這個：

 public void updateOneColumn(String TABLE_NAME, String Column, String rowId, String ColumnName, String newValue){
                 String sql = "UPDATE "+TABLE_NAME +" SET " + ColumnName+ " = "+newValue+" WHERE "+Column+ " = "+rowId;
                 db.beginTransaction();
                 SQLiteStatement stmt = db.compileStatement(sql);
                 try{
                     stmt.execute();
                     db.setTransactionSuccessful();
                 }finally{
                     db.endTransaction();
                 }

        }

我這樣稱呼這個方法：

 db.updateOneColumn("roadmap", "id_roadmap",id,"sys_roadmap_status_mobile_id", "1");

這意味着我想要設置的值1在列sys_roadmap_status_mobile_id時id_roadmap = id.

問題是什么都沒有發生。 我的錯誤在哪里？

Answer 1

簡單的解決方案：

String sql = "UPDATE "+TABLE_NAME +" SET " + ColumnName+ " = '"+newValue+"' WHERE "+Column+ " = "+rowId;

更好的解決方案：

ContentValues cv = new ContentValues();
cv.put(ColumnName, newValue);
db.update(TABLE_NAME, cv, Column + "= ?", new String[] {rowId});

Answer 2

以下解決方案適用於我更新單行值：

public long fileHasBeenDownloaded(String fileName) 
{
    SQLiteDatabase db = this.getWritableDatabase();

    long id = 0;

    try {
        ContentValues cv = new ContentValues();
        cv.put(IFD_ISDOWNLOADED, 1);

        // The columns for the WHERE clause
        String selection = (IFD_FILENAME + " = ?");

        // The values for the WHERE clause
        String[] selectionArgs = {String.valueOf(InhalerFileDownload.fileName)};

        id = db.update(TABLE_INHALER_FILE_DOWNLOAD, cv, selection, selectionArgs);
    } 
    catch (Exception e) {
        e.printStackTrace();
    }
    return id;
}