How to Intercept SQL in Hibernate

rwalsh · **Joined:** Mon May 30, 2005 5:52 am **Posts:** 15

Hi,
I am woudering if it is possible to intercept the SQL before it is set to the database. Reason is I am trying to use EXPLAIN to analyse SQL in POSTGRES. In order to do this I have to append EXPLAIN to the start of each query going to the database. Is there a mechanism for doing somthing like this in hibernate.
thanks,
Richie.

max · **Posted:** Thu Nov 10, 2005 7:08 am

Interceptor.prepareSQL() in 3.1

but adding EXPLAIN while the program runs wont solve anything since hibernate expects to get a result back - not some eXPLAIN result.

rwalsh · **Joined:** Mon May 30, 2005 5:52 am **Posts:** 15

Thanks for that. The EXPLAIN will return results - but has the added bonus of writing EEXPLAIN information about the query to a postgres log file.

max · **Posted:** Thu Nov 10, 2005 7:47 am

ah - didn't know postgress could do that, nice.

then Interceptor.prepareSQL() is your savior ;)

rwalsh · **Joined:** Mon May 30, 2005 5:52 am **Posts:** 15

Hi Max - Im guessing that this method is'nt available in 3.0. Can't find it anyway. If im using 3.0 is there any way around this.

max · **Posted:** Thu Nov 10, 2005 8:22 am

not really, but you can go to AbstractBatcher and you can edit the sql there (you will need to patch it in your own version)

baliukas · **Posted:** Thu Nov 10, 2005 8:31 am

Just wrapp driver and intercept it in JDBC level.

rwalsh · **Joined:** Mon May 30, 2005 5:52 am **Posts:** 15

Yeah,
I think that is what I am going to do. Had started down that road but though Hibernate would have somthing. Unfortunatly we have not upgraded to 3.1 yet so I will do with this.

baliukas · **Posted:** Thu Nov 10, 2005 9:11 am

BTW
if you need query plan only then you can configure postgresql to print it to log without any SQL interception (see debug and profiling options).

rwalsh · **Joined:** Mon May 30, 2005 5:52 am **Posts:** 15

Thanks - Im aware of this. Hibernate also can print the query plan. But I need the Analysis information as well.
Cheers.

cdellinger · **Joined:** Tue Aug 30, 2005 4:43 pm **Posts:** 8

Is it Interceptor.prepareSQL() or prepareStatement()? I'm using the latest 3.1 code but I don't see the prepareSQL method within the Interceptor interface. Am I missing something basic here? Thanks in advance.

max · **Posted:** Fri Nov 11, 2005 3:22 pm

its prepareStatement