I knew I was missing something simple ... doh!  :)

Michal Malecki wrote:

Well, I think you need only simple join in your sql, no extra features of
ibatis needed:
select * from CHILD, PARENT where parent_id=PARENT.id;
am I right?
Michal Malecki



What about relationships from the child up to the parent?  Are they also
classified as N+1?

Suppose we have child table with a fk of parent_id.

if I do:

 SELECT * from CHILD

I'll get a column with parent_id with values.

Now suppose I also want details pertaining to the parent_id along with
the recordset of Child, I need not
do 10 separate selects for the parent ...  is this also an N+1 problem?

What is the preferred iBatis model for this?

Cheers

Abdullah


Kris Jenkins wrote:



friendVU admin wrote:



What is n+1?
.V



n++! :-P

It's when each child object in a complex query has to be selected
seperately.  If 'parent' has 10 'children', you end up with 10+1
select statements being issued.  See the developer's guide under
'Avoiding N+1 selects' for the full lowdown.  Version 2.0.9 comes with
new groupBy goodness to banish the N+1 problem.

Kris








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