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Large Databases  RSS feed

 
M. Marple
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Dear authors,

I read, EJB �s useful when processing large quantities of data?

In what range of data quantities is EJB meaningful?

Is there an upper limit?

Thank you for your attention
 
Mike Keith
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I'm not sure about the context that you heard that in, but I'll take a guess...

The query language of JPA (called JPQL) provides support for a feature called bulk updates and deletes. This means that you can perform operations on large quantities of data in a single operation without going into native SQL and without causing the entities to be loaded into memory.

In general, entities may be mapped to large tables with large data sets. When querying, though, each entity (unless it is in a lazily-loaded relationship) is typically loaded into memory to be processed.
 
Jeroen T Wenting
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Let's see, we have a database server (just one of many) which at the moment has 6GB free diskspace, our monitoring systems are screaming that it's critically short.
We expect that to fill in under a week if the volume of data increases just a little bit (at the moment it's in equilibrium, with expired data being deleted as fast as new data comes in).

EJBs do well handling that.
 
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