BlogJava-何杨的IT技术博客-随笔分类-SQLhttp://www.blogjava.net/heyang/category/53161.html为实现完美而进行探索.zh-cnWed, 26 Dec 2012 03:45:11 GMTWed, 26 Dec 2012 03:45:11 GMT60DB2的COALESCE函数http://www.blogjava.net/heyang/archive/2012/12/24/393397.html何杨何杨Mon, 24 Dec 2012 06:34:00 GMThttp://www.blogjava.net/heyang/archive/2012/12/24/393397.htmlhttp://www.blogjava.net/heyang/comments/393397.htmlhttp://www.blogjava.net/heyang/archive/2012/12/24/393397.html#Feedback0http://www.blogjava.net/heyang/comments/commentRss/393397.htmlhttp://www.blogjava.net/heyang/services/trackbacks/393397.html
用法:
COALESCE(A,B,C,D...);

说明:
若A为空;则取B,若B为空,则取C;...;依此类推.

用例:
        sb.append("    select ");
        sb.append("        COALESCE(t03.EMP_USER_NAME,'') as sellerName,");
        sb.append("        COALESCE(t03.EMP_LOTUS_MAIL,'') as sellerNotesMail,");
        sb.append("        COALESCE(t03.EMP_INTERNET_ID,'') as sellerIntranetId,");
        sb.append("        COALESCE(t04.BUSINESS_UNIT_NAME,'') as busiNessUnit,");
        sb.append("        COALESCE(t02.TOPT_JOB_ROLE_NAME,'') as jobRoleName,");
        sb.append("        t01.TERRITORY_NAME as territoryName");
        sb.append("    from");
        sb.append("        topt.territory  t01");
        sb.append("        left join topt.job_role   t02 on t01.ROLE_KEY=t02.ROLE_KEY  ");
        sb.append("           left join FRS.Resource    t03 on t01.EMP_UID=t03.RESOURCE_EMPLOYEE_UID");
        sb.append("        left join TOPT.BUSINESS_UNIT t04 on t01.BUSINESS_UNIT_KEY=t04.BUSINESS_UNIT_KEY        ");
        sb.append("    where ");
        sb.append("        t01.TERRITORY_KEY=? ");
        String sql = sb.toString();


何杨 2012-12-24 14:34 发表评论
]]>从结果集中取出前1024行(DB2)http://www.blogjava.net/heyang/archive/2012/12/20/393273.html何杨何杨Thu, 20 Dec 2012 12:20:00 GMThttp://www.blogjava.net/heyang/archive/2012/12/20/393273.htmlhttp://www.blogjava.net/heyang/comments/393273.htmlhttp://www.blogjava.net/heyang/archive/2012/12/20/393273.html#Feedback0http://www.blogjava.net/heyang/comments/commentRss/393273.htmlhttp://www.blogjava.net/heyang/services/trackbacks/393273.html Select filed from schema.table where condition  fetch first 1024 rows only

与select top 同等效果.

何杨 2012-12-20 20:20 发表评论
]]>