Once again 'Thank you', I have tried it too, but i have problems like
those described in JIRA:
<>(N + 1) solution does not yield same results as lazy loading solution
http://issues.apache.org/jira/browse/IBATIS-69
I have no more time to experiment what is wrong in my mapping.
I will stay by ugly-but-functional 1+N queries solution.
Jeff Butler wrote:
Ahh - I see. This is a classic example of the N+1 selects
problem. iBATIS has a good solution: use an SQL join and the iBATIS
groupBy feature. This link should help:
Jeff Butler
On 12/5/05, Jozef Hribik <[EMAIL PROTECTED]>
wrote:
Thank
you Jeff, i am using your solution already, but i want to get _categories_with_products_
in single step.
Map map = new HashMap();
map.put("parameterY", parameterY);
map.put("parameterX", parameterX);
List results = sqlMap.queryForList("getCategory", map);
<statement id="getCategory" parameterClass="int"
resultMap="get-category-result">
select * from CATEGORY where CAT_DESCRIPTION like '%$
parameterY$%'
</statement>
<statement id="getProductsByCatId" parameterClass="int"
resultMap="get-product-result">
select * from PRODUCT where PRD_CAT_ID = #value# and PRD_PRICE = #parameterX#
</statement>
Is it possible or is it a new feature request ?
Jeff Butler wrote:
Here's how to do it with a map:
Map map = new HashMap();
map.put("parameterY", parameterY);
map.put("parameterX", parameterX);
List results = sqlMap.queryForList("getProductsByCatId",
map);
<select id="getProductsByCatId"
parameterClass="java.util.Map"
resultMap="get-product-result">
select * from PRODUCT where PRD_CAT_ID = #
parameterY# and PRD_PRICE = #parameterX#
</select>
You could also do it with a POJO as your parameter class
(which is preferred) - the properties in the select statement
correspond to properties in your POJO.
Jeff Butler
On 12/2/05, Jozef Hribik <[EMAIL PROTECTED]
> wrote:
I
would like to pass an additional parameter to filter a collection
property.
I will use an example from iBATIS-SqlMaps-2.pdf, page 27.
How can i select a category with products with certain price specified
by parameterX?
<resultMap id="get-category-result"
class="com.ibatis.example.Category
">
<result property="id" column="CAT_ID"/>
<result property="description" column="CAT_DESCRIPTION"/>
<result property="productList" column="CAT_ID"
select="getProductsByCatId"/>
</resultMap>
<statement id="getProductsByCatId" parameterClass="int"
resultMap="get-product-result">
select * from PRODUCT where PRD_CAT_ID = #value# and PRD_PRICE = #parameterX#
</statement>
Thanks
Jozef
|
