Named Query or Native Query

Question

Hello,
I am using native query to search for results on my search page. A friend of mine just told me that I better use named query or the time to get my search results will be too slow.
Does Named Query give you faster result than Native Query?
Thanks in advance.
Regards,
Hemen

Answer 1

When you define named queries (note that this is a Hibernate example) you can put them in for example XML,
<query name="findItemsByDescription">
<![CDATA[from Item item where item.description like :desc]]>
</query>or a SQL query like
<sql-query name="findItemsByDescription">
<return alias="item" class="Item"/>
<![CDATA[select {item.*} from item where description like :desc]]>
</sql-query>You can call these queries by using the same code, for example,
session.getNamedQuery("findItemsByDescription").setString("desc", description);This is what is being meant by sharing the same calling API.
When taking about performance. You have to know something about what goes on under the hood.
You have probably programmed something using straightforward JDBC, so you know how to queries
get passed to the driver and send to the database. When using HQL or JPA-QL the queries first have
to be parsed into an SQL language that the database can understand. In this case, we have an extra
parsing step in between. Note that Native SQL queries, including stored procedure calls, the persistence
framework still takes care of mapping the JDBC result sets to graphs of persistent objects.
If you want to include a native SQL hint to instruct the database management systems query optimizer,
for example, you need to write the SQL yourself. HQL and JPA-QL do not have keywords for this.
The disadvantage of putting native SQL in your mapping metadata is lost database portability, because
your mappings, and hence your application, will work only for a particular database. But usually this is of a
minor concern as you are probably not creating a framework that has to work on every database.
When you want to get behind the performance of your query, you really have to consult the database
and look at the execution plan - A DBA can tell you exactly what is good and what can be optimized.