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案例讨论:Oracle两表连接

dn001
Oracle的两表连接怎么实现,原来是SQL的现在想换成oracle的,SQL的如下:   SELECT COUNT(*) AS COUNT, SUM(timelen) AS totlekeeptime, SUM(moneys) AS totletimefee, SUM(realmoneys) AS totlenewfee, areacode.area_name FROM phonedata INNER JOIN areacode ON LEFT(phonedata.ani, LEN(areacode.area_code)) = areacode.area_code WHERE starttime>'2005-12-27 00:00:00' and starttime<'2005-12-27 23:59:59' and endtime is not null and userid like '001136' GROUP BY areacode.area_name order by totlekeeptime   oracle里该怎么办呢?   讨论一:   SELECT AREACODE.AREA_NAME,COUNT(*) AS COUNT,   SUM(TIMELEN) AS TOTLEKEEPTIME,   SUM(MONEYS) AS TOTLETIMEFEE,   SUM(REALMONEYS) AS TOTLENEWFEE,   FROM PHONEDATA INNER JOIN AREACODE ON (LEFT(PHONEDATA.ANI,LEN(AREACODE.AREA_CODE)) = AREACODE.AREA_CODE)   WHERE STARTTIME>'2005-12-27 00:00:00'   AND STARTTIME<'2005-12-27 23:59:59'   AND ENDTIME IS NOT NULL   AND USERID LIKE '001136%'   GROUP BY AREACODE.AREA_NAME   ORDER BY TOTLEKEEPTIME   /   说明:只是不知道你没有限定哪个表的那些字段是不是只有一个表里面有,假如不是,会报错的。   点评:有错误:   1.oracle里两表连接不是用INNER JOIN AREACODE ON 而是用外连接LEFT OUTER JOIN .. ON或内连接LEFT in JOIN .. ON   2.oracle里没有LEFT函数,取字接数是用length;   讨论二:   SELECT AREACODE.AREA_NAME,COUNT(*) AS COUNT,   SUM(TIMELEN) AS TOTLEKEEPTIME,   SUM(MONEYS) AS TOTLETIMEFEE,   SUM(REALMONEYS) AS TOTLENEWFEE,   FROM PHONEDATA ,AREACODE   where substring(PHONEDATA.ANI,1,length(AREACODE.AREA_CODE)) = AREACODE.AREA_CODE   and to_date(STARTTIME,'yyyy-mm-dd hr24:mi:ss')>'2005-12-27 00:00:00'   AND to_date(STARTTIME,'yyyy-mm-dd hr24:mi:ss')<'2005-12-27 23:59:59'   AND ENDTIME IS NOT NULL   AND USERID LIKE '001136%'   GROUP BY AREACODE.AREA_NAME   ORDER BY TOTLEKEEPTIME   点评:两表连接那错了,但这地方: substring(PHONEDATA.ANI,1,length(AREACODE.AREA_CODE)) = AREACODE.AREA_CODE是对的;   最佳答案:   SELECT COUNT(*) AS COUNT, SUM(timelen) AS totlekeeptime, SUM(moneys) AS totletimefee,   SUM(realmoneys) AS totlenewfee, areacode.area_name   FROM phonedata ,areacode   WHERE starttime>'2005-12-27 00:00:00' and starttime<'2005-12-27 23:59:59'   and endtime is not null and userid like '001136'   /*and LEFT(phonedata.ani, length(areacode.area_code)) = areacode.area_code */   and substr(phonedata.ani, 1,length(areacode.area_code)) = areacode.area_code   GROUP BY areacode.area_name order by totlekeeptime   说明:inner join 直接相等就可以了,left换成substr。

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