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Hi Michelle,
I'm not convinced that it's a JPOX bug here. I'll explain why Let's take the example of MapStringValueCollections, and its field "MapOfObject_String3". This is defined as a Map field with join table and with key of SimpleClass, value of String. Both key and value are embedded, so the join table will have * FK back to the owner table (IDENTIFIER) * column for the value * column(s) for the key fields This is all well and good, but is missing one thing. JPOX needs to put a PK on the join table. What are you proposing that it uses ? It doesnt have an id for the (embedded) SimpleClass key. So it needs something else - and in this case it adds this ADPT_PK_IDX column. Is there a field in the key class (SimpleClass) that would give uniqueness ? e.g "ID" ? In that case you should define the <primary-key> on the join table to be formed by IDENTIFIER and ID. This should be enough to stop JPOX adding its own PK adapter column (and if it doesnt prevent it then it is indeed a bug in JPOX). If there isn't a field of that nature then you have to have the ADPT_PK_IDX, or the JDO impl needs to be told somehow that it should not create a PK on the join table (which should be the last option IMHO since its a best practice to have one). I noticed that in the TestHashSetCollections/TestSetCollections you added <order> which avoided this issue. This means that you have a HashSet/Set that can't contain duplicates (since its a Set), and a datastore representation that *can* have dups. Using a join table primary-key specification (like that above) there would have been better IMHO. 1. Let's take the example of application identity for MapStringValueCollections, and its field "MapOfObject_String3".
The key for this map is SimpleClass. The metadata for SimpleClass says that the primary key field of the class is "id". So JPOX knows that there is a key object embedded in the join table that has a primary key field, and that field can be used as the primary key of the join table. 2. Take the case of datastore identity for MapStringValueCollections, and its field "MapOfObject_String3". The key for this map is SimpleClass. The metadata for SimpleClass doesn't identify a primary key (duh. It's datastore identity). So JPOX has no idea that there is a key field in the key object. Therefore, the orm metadata needs to identify a key column for the join table, and I'd suggest using the id column as the key, as Andy suggests. Sadly, the HashSetCollections and SetCollections have <order> columns which is not correct. There should not be an ordering specified for the join table since duplicates are not allowed. So the mapping for application identity should not need a primary key but the datastore identity mapping does need a primary key (and again, I'd use the id field of SimpleClass as the join table key column. Agree with Craig wrt app identity. JPOX should (and indeed does in JPOX CVS - builds 15/11/2005 onwards) use the app id fields of the key as part of the PK when the user hasn't specified the PK, so no need to add the PK spec for that identity case.
It shows up some schema mapping issues. For example in HashMapStringValueCollections (app identity) there is a field HashMapOfSimpleClass_String12 that has an embedded key (SimpleClass), which has no <embedded> definition, and which has a schema consisting of a single column for that embedded key. It also gets through to the actual test of expected versus actual on MapStringValueCollections (app identity) with the failure being in the comparison process - the values are correct by my reckoning Checked in various metadata changes that resolve some of the problems in application identity. -- revision 345289.
The attached patch adds a pk to the id column of join tables for SimpleClass fields for datastore identity. JPOX still gives the same error with this patch applied:
SQL Exception: 'ADPT_PK_IDX' is not a column in table or VTI 'DATASTOREIDENTITY0.HASHMAP_OBJECT3_STR'. SQL Exception: 'ADPT_PK_IDX' is not a column in table or VTI 'DATASTOREIDENTITY0.HASHTBL_OBJECT3_STR'. SQL Exception: 'ADPT_PK_IDX' is not a column in table or VTI 'DATASTOREIDENTITY0.MAP_OBJECT3_STR'. SQL Exception: 'ADPT_PK_IDX' is not a column in table or VTI 'DATASTOREIDENTITY0.TREEMAP_OBJECT3_STR'. This appears to be a JPOX issue assuming a column that doesn't exist.
Committed patch with revision 345615.
I see that the MetaData is now, for example
<field name="HashMapOfObject_String3" table="HASHMAP_OBJECT3_STR"> <join column="IDENTIFIER"/> <key> <embedded> <field name="id" primary-key="true" column="ID"/> <field name="intField" column="INTVAL"/> <field name="stringField" column="STRINGVAL"/> </embedded> </key> <value column="VALUEVAL"/> </field> That certainly doesnt agree with my definition of a PK specification for the join table. It should be (IMHO) like this <join> <primary-key> <column name="IDENTIFIER"/> <column name="ID"/> </primary-key> </join> which nicely defines the colums to be used for the join table. Using fields of an embedded object and specifying primary-key there is not logical to me, and not supported by JPOX either. The JPOX online docs http://www.jpox.org/docs/1_1/constraints.html provides what we support for PK definition, which is that above. Combining the metadata for the field, join, key, and value, I come up with this:
<field name="HashMapOfObject_String3" table="HASHMAP_OBJECT3_STR"> <join column="IDENTIFIER"/> <primary-key> <column name="IDENTIFIER"/> <column name="ID"/> </primary-key> </join> <key> <embedded> <field name="id" column="ID"/> <field name="intField" column="INTVAL"/> <field name="stringField" column="STRINGVAL"/> </embedded> </key> <value column="VALUEVAL"/> </field> This should be a standard, portable mapping for the map<embedded SimpleClass, embedded String> case. I will propose to the expert group that a portable mapping for arrays, collections, and maps will include a primary key on the join table. The expert group rejected the notion that a portable mapping for arrays, collections, and maps will include a primary key on the join table. So there is no need in general to include a primary key element.
But we still need to map these fields that use an embedded SimpleClass as a Map key or Set element. These fields should include a primary key in the mapping. Remapped relevant fields as specified in the comments. Tests pass except one, for which there seems to be an unrelated problem. revision 351537
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However, JPOX still wants an adapter index column in the schema for embedded PC fields (see
JDO-121for a discussion). Since Map does not allow duplicates, and MapStringKeyCollections pass without an order column such as we used to map Collections, it seems that this is a JPOX bug.