1 Reply Latest reply on Apr 20, 2004 11:43 AM by Alexey Loubyansky

    left-join descriptor is problematic

    Alexey Loubyansky Master

      Repost of https://sourceforge.net/tracker/?func=detail&atid=376685&aid=937767&group_id=22866

      I applaud the new the left-join read ahead option but
      the xml descriptors in jbosscmp-jdbc.xml are difficult
      to configure. reasons for descriptor change are:

      1.) for each query I wish to left-join, I have to
      specify the cmr fields each time which leads to
      redundancy. grouping the joins is more logical like
      load-groups are handled.

      2.) writing xdoclet support is non-trivial for the
      current left-join descriptors.

      so I propose the syntax change from, for example,

      <read-ahead>
      on-find
      <eager-load-group>report</eager-load-group>
      <left-join cmr-field="lineItems"/>
      <left-join cmr-field="product"
      eager-load-group="short"/>
      </left-join>
      <left-join cmr-field="customer"
      eager-load-group="basic"/>
      </read-ahead>

      to

      <read-ahead>
      on-find
      <eager-load-group>report</eager-load-group>
      <left-join-group>group_a</left-join-group>
      </read-ahead>

      <left-join-groups>
      <left-join-group>
      group_a
      example left join group
      <left-join>
      <cmr-field>lineItems</cmr-field>
      <left-join>
      <cmr-field>product</cmr-field>
      <eager-load-group>short</eager-load-group>
      </left-join>
      </left-join>
      <left-join>
      <cmr-field>customer</cmr-field>
      <eager-load-group>basic</eager-load-group>
      </left-join>
      </left-join-group>
      </left-join-groups>

      in addition, maybe "left-join" should be renamed to
      "relation-join" for clarity.