Originally posted by Niranjan Deshpande:
Plesae refer Oreilly - Page 107
All the three things - pkColumnName valueColumnName pkColumnValue are confusing me.
Functionally, what is the difference between these three.
It would be great if some one draws a relevant table here and explains me
The schema is simple as a pie.
Have a look at the following table:
So, the layout is:
pkColumnName = "PK_COLUMN"
valueColumnName = "VALUE_COLUMN"
pkColumnValue = "DETERMINANT2" (for example)
The idea is each row in the table represents certain entity and there must be the way to distinguish between entities (3 entities in the preceding example)
[ February 09, 2008: Message edited by: Alex Kikhtenko ]
Suppose we have another one entity Product:
As you can see we want the both entities to use the same table GENERATOR_TABLE to hold their Primary-Key-Next-Value.
Suppose also we've just persisted 3 Customer entities and 8 Product entities into the DB.
In this case the GENERATOR_TABLE table would look like:
So obviously CUST_ID is necessary to distinguish it's primary key value from primery key value of Product entity bean.
Hope this helps.