How to do select the data in batches using hibernate?

问题

I have a function which basically returns the entire data from the table.How can i implement batch fetching so that the data will be returned in batches of 60,000 rows at a time.

Will the following logic applicable in this scenario?

http://javainnovations.blogspot.com/2008/07/batch-insertion-in-hibernate.html

回答1:

In hibernate.properties, set the batch size using the parameter

hibernate.jdbc.batch_size= 'your_value'

回答2:

To select data in a batch, you can apply data pagination by setting the initial position & the number of results to be fetched for a query.

for(int i=0; i < MAX_SIZE; i = i + BATCH_SIZE){

    List<Object> resultList = entityManager.createQuery(SQL_QUERY).setFirstResult(i).setMaxResults(BATCH_SIZE).getResultList();

    //-- Batch Computation
} 

I have provided sample code, can modify it accordingly.

回答3:

To select the data with hibernate, in hibernate.properties, set the fetch size using the parameter:

hibernate.jdbc.fetch_size= SOME_VALUE

or in the query:

.setFetchSize(SOME_VALUE)

if you are updating data use: the batch_size

hibernate.jdbc.batch_size= SOME_VALUE

来源：https://stackoverflow.com/questions/9570518/how-to-do-select-the-data-in-batches-using-hibernate