Criteria.addSelectColumn problem

[Frank Nguyen <fr...@sbcglobal.net>]

I have 3 tables,  t1, t2 and t3.  t3 table is just a join-ref table of t1 and t2 in such a way that t3.c2 is ref index to t1.c1 and t3.c3 is a ref index to t2.c1 (t3.c1 is index for t3 table). Thus, table t3 has many records w/ same value in column 2 and 3. What I want is to select only rows from table 3 with unique c3 values. The statement:

"select * distinct from t3 where t3.c2 = 3333"

gives me 27 rows where many of them have the same c2=3333 and c3=same number, obviously. (i.e.   3333 4532, 3333 4532, 3333 4533, 3333 4534, etc.) which is not what I wanted.

All I want is to have distinctive rows with c3 unique. So, the following statement gives me exactly what I want:

select c3 distinct from t3 where t3.c2=3333

gives me 7 row with c3 distinctive (i.e. 3333 4532, 3333 4533, 3333 4534, etc.)

However, when I do it in Torque:

crit.add (c2, 3333)
crit.addSelectColumn (c3)
crit.setDistinct();
Iterator results = t3Peer.doSelect(crit).iterator() 

would throw Exception at doSelect() because during the populateObject(), it found only 1 column instead of all columns as default to populate the data into it. 

So, to make it short, is there a way to select records from a table with a specified, distinctive column(s) in Torque?

Thanks in advance,


  

Frank Nguyen
(408) 836-6235 (Cell)

RE: Criteria.addSelectColumn problem

[Thomas Fischer <fi...@seitenbau.net>]

> crit.add (c2, 3333)
> crit.addSelectColumn (c3)
> crit.setDistinct();
> Iterator results = t3Peer.doSelect(crit).iterator() 
> 
> would throw Exception at doSelect() because during the 
> populateObject(), it found only 1 column instead of all columns as 
> default to populate the data into it. 

Alternatice to Carl's answer:
If you want the complete objects instead of just the values of c3, xou 
want to use a subselect. You express the condition in the subselect, and 
then select all the objects in the outer select. Like

innercrit.add (c2, 3333)
innercrit.addSelectColumn (c3)
innercrit.setDistinct();
crit.add(c2, 3333);
crit,add(c3, innercrit);
Iterator results = t3Peer.doSelect(crit).iterator();

Hope this works (have not tried it), but in principle it is possible.

   Thomas

RE: Criteria.addSelectColumn problem

["Manaster, Carl" <Ca...@ACTIVX.com>]

Hi, Frank,

> However, when I do it in Torque:
> 
> crit.add (c2, 3333)
> crit.addSelectColumn (c3)
> crit.setDistinct();
> Iterator results = t3Peer.doSelect(crit).iterator() 
> 
> would throw Exception at doSelect() because during the 
> populateObject(), it found only 1 column instead of all 
> columns as default to populate the data into it. 
> 
> So, to make it short, is there a way to select records from a 
> table with a specified, distinctive column(s) in Torque?

I think what you are looking for is to replace t3Peer with BasePeer.
This will not return t3 records; instead it will return just generic
Records, and those records will hold only the specified (c3) select
column.

Peace,
--Carl

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