数据库联表查询sql语句

string tempsql2 = "select a.tid,a.click,b.newsId,b.newstitle,b.addate "
    + " from Tdayclick a inner join ncar_news b on a.tid = b.newsid where a.type = 1 and a.adddate = " + yday + " order by a.click desc";

 string tempsql4 = "SELECT c.newsId, c.newsTitle,c.adddate, d.snum "
                + " FROM ncar_News c INNER JOIN "
                + "           (SELECT a.tid, a.click + b.tnum AS snum "
                + "          FROM (SELECT tid, click "
                + "                  FROM TDayClick "
                + "                  WHERE (type = 1) AND (adddate = " + YDay + ")) a INNER JOIN "
                + "                    (SELECT tid, COUNT(*) AS tnum "
                + "                   FROM TClick "
                + "                   WHERE (type = 1) "
                + "                   GROUP BY tid) b ON a.tid = b.tid) d ON c.newsId = d.tid "
                + " WHERE (c.isDelete = 0) OR "
                + "       (c.isDelete IS NULL) "
                + " ORDER BY d.snum DESC ";