Query vs Criteria

Soulstealer · **Joined:** Thu Jan 25, 2007 5:31 am **Posts:** 8

I was reading in the hibernate documentation about Query and Criteria
but I couldn't find which is better for what
the doc says that if you prefer to use object oriented method for querying db instead of building string query you can use Criteria
I'm asking:
which is better for what ?
and which is faster for what ?
and which is best practice and so on...

i92absaj · **Posted:** Thu Jan 25, 2007 8:44 am

Hello,
(first of all, sorry about my english)

I started using HQL Query. From my point of view, if you have an idea about SQL it's easier to devolop some applications than using Criteria. However, I found some cases where Criteria makes life easier.

For instance, If you want to add restrictions to a query dinamically. I think it's easier to use Criteria. Imagine that you should create a query which depends on the restrictions a user selected on your front-end.

Imaging user want to obtain information using restriction 1:

Code:

        createCriteria c
        If (user want restriction 1)
          c.add(Restrictions 1)
        If (user want restriction 2)
          c.add(Restrictions 2)
        c.list

When using HQL you have to code the restriction handly, and you have to control several aspect tha Criteria do

Code:

       query=" where "
        If(user want restriction 1)
           query = query + "restriction 1 ..."
        If(user want restriction 2)
           query = query + "restriction 2 ..."

        createQuery q ("select * from "+query).list

I hope help you :-S

Soulstealer · **Joined:** Thu Jan 25, 2007 5:31 am **Posts:** 8

OK, so which is faster ?

i92absaj · **Posted:** Thu Jan 25, 2007 9:42 am

Soulstealer wrote:

OK, so which is faster ?

Boht Criteria and HQL should translate to SQL language.
So, as far as I know SQL (createSQLQuery()) should be the fastest method.

kochcp · **Posted:** Thu Jan 25, 2007 10:12 am

I try to use Query in all cases as it's just easier to write b/c hql is so similar to sql. The only time I use Criteria is when I need a dynamically built query from user input, need to perform a transformation, or need to override some lazy settings.