Android Sqlite选择带有int值的args []

Question

在我的DBHelper的getEvents方法中有这行代码.

    int year, month, day;
    String[] columns = new String[] { KEY_EVENTNAME, KEY_DESCRIPTION,
            KEY_HOUR, KEY_MINUTE, KEY_DAY, KEY_MONTH, KEY_YEAR,
            KEY_REMINDER };
    Cursor c = database.query(DATABASE_TABLE, columns, 
            KEY_YEAR + "=?"+ " AND " + KEY_MONTH + "=?" + " AND "+ KEY_DAY + "=?",
            new String[] {String.valueOf(year), String.valueOf(month), String.valueOf(day)}, 
            null, null, KEY_MONTH + " AND "
            + KEY_DAY);

它总是什么都不返回.当我删除以下内容时

    int year, month, day;
    String[] columns = new String[] { KEY_EVENTNAME, KEY_DESCRIPTION,
            KEY_HOUR, KEY_MINUTE, KEY_DAY, KEY_MONTH, KEY_YEAR,
            KEY_REMINDER };
    Cursor c = database.query(DATABASE_TABLE, columns, 
            KEY_YEAR + "=?",
            new String[] {String.valueOf(year)}, 
            null, null, KEY_MONTH + " AND "
            + KEY_DAY);

它运行正常.我的代码有什么问题？它似乎不接受多个值作为where子句.谁能帮我这个？谢谢.

Answer 1

答案在标题中:您试图将整数值传递给查询,但实际上您最终得到的是字符串值.

这是Android数据库API中一个可怕的设计错误; 您只能将参数用于字符串.

整数不具有字符串值可能具有的格式和SQL注入问题,因此您只需将数字直接插入SQL表达式:

Cursor c = database.query(
    DATABASE_TABLE, columns, 
    KEY_YEAR  + "=" + year  + " AND " +
    KEY_MONTH + "=" + month + " AND " +
    KEY_DAY   + "=" + day,
    null, null, null,
    KEY_MONTH + "," + KEY_DAY);

(而且orderBy语法错了.)