Question

I have a table with four columns, say

P_Key(int), Ref_Key(int), Key(String), Value(Integer).

I want to avoid multiple create statements by persisting a map along with Ref_key into this database. Map contains keys and corresponding value.It will create multiple row for that Ref_key using entries from the map.I am using hibernate.

Suppose, I want to persist following map :

"Me" -> 0
"You" -> 10
"They" -> 12

and Ref_Key is 123.

Then it should create 3 rows into table.

P_Key Ref_Key Key Value
1      123    "Me" 0
2      123    "You" 10
3      123    "They" 12

Assuming that key starts with 1 and is auto-incremented.

What is the approach that I should follow?

Answer 1

If you mean “insert statements” instead of “create statements“; I am not sure you can: a database has to receive 3 INSERTs for adding 3 lines in the database. But Hibernate should merge them and send only 1 network request (batching of requests).

The approach I suggest:

• Create an @Entity with the table format.
• Create one instance of your entity for each element of your map.
• Simply persist all the instances.
• Close your transaction (I mean flush).

See http://docs.jboss.org/hibernate/orm/3.3/reference/en/html/batch.html for more information about batching. NOTE: Unfortunately, Hibernate disables the batching for the auto incremented primary keys!