sqllite 文件

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查詢(xún)語(yǔ)句

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  SELECT * FROM images WHERE tile_id in (SELECT tile_id FROM map  where tile_column= ? and tile_row = ? and zoom_level = ?);

    public byte[] queryMapImage(int x, int y, int zoom) {
        MapInfo mapInfo = null;
        openDB();
        try {
            String tile_column = String.valueOf(x);
            String tile_row = String.valueOf(y);
            String zoom_level = String.valueOf(zoom);
            //  String sql = "select * from  map  where  tile_column= ? and tile_row = ? and zoom_level = ?";
            String sql = "SELECT * FROM images WHERE tile_id in (SELECT tile_id FROM map  where tile_column= ? and tile_row = ? and zoom_level = ?);";
            Cursor cursor = mDB.rawQuery(sql, new String[]{tile_column, tile_row, zoom_level});
            byte[] jpgData = null;
            while (cursor.moveToNext()) {
                String tile_id = cursor.getString(cursor.getColumnIndex("tile_id"));
                jpgData = cursor.getBlob(cursor.getColumnIndex("tile_data"));
            }
            cursor.close();
            return jpgData;
        } catch (Exception e) {
            e.printStackTrace();
            LogUtils.e(e.toString());
        }
        return null;
    }

調(diào)用傳給web界面

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