FindByPrimaryKey compiled OK but retuns null for a pre-existing value, WHY?

Question

Hi My name is KV Moorthy.
I have this requirement that one of column shoud have unique value. I had a unique constraint on the table , this ends with ugly error that it comes with NULL pointer error, on the detail it display the CONSTAINT violated. I do not like it.
So i decide to use the FindByPrimaryKey method. ( suppose to check cache and Database).
It did not work logically. When debugged the following code the FindByPrimaryKey method retuns a null value but the value is in cache and DB.
I had define this Entity Attribute as Primary Key. ( i am using the seeded message, when works i was going to define the custom one)
Hello Experts , Please help me ( i am on 11i RUP7) LevelValue is the attribute on my entity object.
public void setLevelValue(String value)
if (getLevelValue() != null)
throw new OAAttrValException(OAException.TYP_ENTITY_OBJECT,
getEntityDef().getFullName(), // EO name
getPrimaryKey(), // EO PK
"LevelValue", // Attribute Name
value, // Attribute value
"AK", // Message product short name
"FWK_TBX_T_EMP_ID_NO_UPDATE"); // Message name
if (value != null)
OADBTransaction transaction = getOADBTransaction();
Object[] itemKey = {value};
EntityDefImpl itemDefinition = ItemSubsEOImpl.getDefinitionObject();
ItemSubsEOImpl item =
(ItemSubsEOImpl)itemDefinition.findByPrimaryKey(transaction, new Key(itemKey));
if (item != null)
throw new OAAttrValException(OAException.TYP_ENTITY_OBJECT,
getEntityDef().getFullName(), // EO name
getPrimaryKey(), // EO PK
"LevelValue", // Attribute Name
value, // Attribute value
"AK", // Message product short name
"FWK_TBX_T_EMP_ID_UNIQUE"); // Message name
setAttributeInternal(LEVELVALUE, value);
}

Answer 1

KV Moorth,
I have this requirement that one of column shoud have unique value. I had a unique constraint on the table ,
this ends with ugly error that it comes with NULL pointer error, on the detail it display the CONSTAINT
violated. Hope u must have mapped the Unique Attribute of the VO to a Field in Page.
Share the exact error stack.
Regards,
Gyan