First of all , let me clear my point of view.
I am working on Seamless upgrade of a project. The Project Uses hibernate and oracle.
My Task is to upgrade the db from version1 to version 2 while project is running.
In Our projects we have a packages containing trigger which will insert a row in Update_table on updating or deletion of any row of specific tables ..suppose t1, t2 , t3.
In version 2 we have some new columns in update_table, and in T1 and t2 too.
and some updates in T1,and t3.
In Upgrade of Db , I am adding column in update_table then i am adding columns in T1.t2,
then I am upgrading of all procedures and triggers by create or replace procedure.
But while updating procedures, i got blocked. it keeps on waiting for several hours.
but when i stop my project after some time , migration process start again and successfully upgrade the procedures.
for further info , My project is also changing values in 1 and t2 frequently.
but when i start my migration process , all update request goes in idle state and after some time it gives connection time out.
I am totally confused in it ..
and one more thing it runs successfully with very less request on projects for updating of table values of t1 and t2