我是Android的新手.实际上,我想从内容提供商和内容解析器查询媒体提供商的数据.
c = mContent.query(CONTENT_URI,projection,where,null,null);
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我的问题是,我如何使用GROUP BY子句从媒体提供者查询数据如下:
select DISTINCT _id, count(_id), _data FROM aaa_table WHERE _data LIKE "A" OR _data LIKE "B" GROUP BY _id;
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我曾尝试设置projection与where如下:
final String[] projection = new String[] {
"_id",
"COUNT ("+ _id +")" ,
"_data"
};
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并且where:
_data LIKE "A" OR _data LIKE "B"
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但是,我找不到如何设置查询选项GROUP BY _id.
请帮我.