Retrieve SQL using an optional condition

Question

Hi,
Ive just created two tables that sql I describe below:
CREATE TABLE "TEST"
    "NAME" VARCHAR2(255 BYTE),
    "LEVEL1" VARCHAR2(255 BYTE),
    "LEVEL2" VARCHAR2(255 BYTE),
    "LEVEL3" VARCHAR2(255 BYTE),
    "CODE"   NUMBER
CREATE TABLE "TEST2"
    "LEVEL1" VARCHAR2(255 BYTE),
    "LEVEL2" VARCHAR2(255 BYTE),
    "LEVEL3" VARCHAR2(255 BYTE)
     ) and then Im going to populate them
INSERT INTO TEST VALUES('0.31 ACQUISITION','7722',     'foc',     NULL     ,1);
INSERT INTO TEST VALUES('0.32 ACQUISITION','7733',     'foco',     NULL     ,2);
INSERT INTO TEST VALUES('0.33 ACQUISITION','7700',     'house',     'class'     ,3);
INSERT INTO TEST2 VALUES('7733',null,null);
INSERT INTO TEST2 VALUES(null,'foco','teka');
INSERT INTO TEST2 VALUES('7733','foco',null);
INSERT INTO TEST2 VALUES('7700','house',null);
INSERT INTO TEST2 VALUES('7700',null,null);I would like to know if its there any way to obtain the desired code joining these tables,
this result consist in the followings conditions:
the levels can be macth or not, but if in any level match, the desired
record will be that one what has value in the higher level
therefore the desired test table record is
'0.32 ACQUISITION','7733',     'foco',     NULL     ,2Is there any way to obtain it using SQL.
Thanks in advanced...

Answer 1

Maybe (NOT TESTED!)
select name,level1,level2,level3,code,
  from (select t.name,t.level1,t.level2,t.level3,t.code,
               rank() over (order by '3'||case when t.level3 = t2.level3 then '1' else '0' end ||
                                     '2'||case when t.level2 = t2.level2 then '1' else '0' end ||
                                     '1'||case when t.level1 = t2.level1 then '1' else '0' end
                            desc
                           ) rnk
          from test t,
               test2 t2
         where t.level1 = t2.level1
            or t.level2 = t2.level2
            or t.level3 = t2.level3
where rnk = 1Regards
Etbin
Edited by: Etbin on 26.11.2011 6:44
Rereading the post seems I missed it :( you need just the one with the value (no need to be a the matching one)
select name,level1,level2,level3,code,
  from (select t.name,t.level1,t.level2,t.level3,t.code,
               rank() over (order by nvl2(t.level3,'1','0') ||
                                     nvl2(t.level2,'1','0') ||
                                     nvl2(t.level1,'1','0')
                            desc
                           ) rnk
          from test t,
               test2 t2
         where t.level1 = t2.level1
            or t.level2 = t2.level2
            or t.level3 = t2.level3
where rnk = 1