We are modernizing the legacy oracle forms to microservices(spring boot/REST API's)
in few table inserts the triggers are throwing post insert errors, and the current team is suggesting to use
begin
HST9I.qms_transaction_mgt.open_transaction( p_trans_opened_by => 'FORM');//(trigger code)
our updates to tables here
HST9I.qms_transaction_mgt.close_transaction( p_trans_opened_by => 'FORM');
end;//trigger code
But as we have the connections and transactions managed by spring, how can we close/open the connections like above.
Any suggestions on how to approach?
Related
I am creating an MVC application using Oracle's Entity Framework, and am writing a bit of code to iterate through all relevant DBLinks and testing them out, returning a grid of results (success/fail). My problem is that after using the fourth DBLink, I get an error "ORA-02020: too many database links in use".
I have tried to explicitly close each DBLink after using it ("alter session close database link LinkName"), but I then receive an error "ORA-02080: database link is in use".
I have tried issuing "COMMIT" statement before attempting to close the DBLink, but that doesn't change the error ("database link is in use").
I have tried to closing the database connection, but I still receive the "database link is in use" error when I create a new connection and try to close the DBLink.
Unfortunately, increasing the number of DBLinks available (open_links, open_links_per_instance) is not an option.
Has anyone seen this with Entity Framework and discovered a solution? Does anyone have any ideas of what else to try?
VICTORY! I found that if I set "Pooling=false" in my connection string, then this error goes away in all of the offending scenarios. This is viable for me since this is just used to test the DBLinks on demand, so I can safely turn off pooling in this scenario. Thanks so much for your responses. I was ready to turn in the towel and admit defeat
To see how many db links are open i syour session use the GV$DBLINK view
select DB_LINK from GV$DBLINK;
DB_LI
-----
LEDRP
YDO
To close a db link you must do two things.
First commit or rollback the transaction. Note that even if you do not change anything a transaction is open due to the use of the DB LINK.
Second you must CLOSE DATABASE LINK using the ALTER SESSION statement.
rollback;
ALTER SESSION CLOSE DATABASE LINK LEDRP;
You see, that link is closed and appears not in the view:
select DB_LINK from GV$DBLINK;
DB_LI
-----
YDOV
I have a JBoss 6 application running both EJB and Spring code (some legacy involved in this decision). It should communicate to Oracle and PostgreSQL databases, on demand.
JPA is the way DB operations are done, no direct JDBC is involved.
I would like to do the following: without altering the business logic, to be able to "silence" database updates/deletes from my application, without breaking the flow with any exceptions.
My current thoughts are:
Set the JDBC driver as read-only from the deployment descriptor - this works only with PostgreSQL (Oracle driver does not support this)
Make a read-only user on the RDBMS level - it might fill me up with errors
Make all transactions rollback instead of committing - is this possible?
Make entity manager never persist anything - set the FlushMode to MANUAL and make sure flush() never gets called - but commit() still flushes everything.
Is there any other concise approach to this?
If you want to make sure the application works as on production, work on a replica of the Database. Use a scheduler every night that overwrites the replica DB.
My request also includes the need for this behavior to be activated or deactivated at runtime.
The solution I found (currently for a proof-of-concept) is:
create a new user, grant him rights on the default schema's tables;
with this user create views for each of the tables, with the same name (without the schema prefix);
create a trigger for each view that does nothing on insert, update, or delete, using INSTEAD OF;
create a data source and persistence unit for this user;
inject two entity managers at runtime, use the one that is needed;
Thanks for your help!
I have a WCF service that uses Microsoft Enterprise Library Logging to log some messages to the Event Log. That works just fine.
The problem is that i want to log some messages to a table in an Oracle database. I am using the Entity Framework to communicate with that Oracle database.
The next step is a right click on the 'web.config' and choose the option 'Edit Enterprise Configuration'. I get the 'Enterprise Library Configuration' editor. In there i am trying to set the Logging Settings so that it also logs to the database, but when i add a database trace listener it´s asking me to fill in a procedure name. Do i have to add a procedure name to fill the table in Oracle? The msdn tells me to run the script that create an MSSQL database 'Logging' and some tables. But i don't have an MSSQL server, i have an Oracle server. And i don't want to use a seperate logging database, but save the logs to a single table.
Can anybody help me with this?
Kind regards
The Enterprise Library Database Trace Listener uses 2 stored procedures to write to the database: Add Category Procedure and Write To Log Procedure.
There is a SQL Server script to create the tables and stored procedures. This would have to be ported to Oracle.
Unfortunately, it looks like this does not work as easily as you would hope. See the blog post, Enterprise Library Logging to Oracle Database (this is based on EntLib 3, I believe) and the work item Cannot log to oracle Database using logging blocks for a description of some of the issues as well as some downloads to help.
Try to be more clear, I'm in lack of ideas in this problem, even it sounds like a classic.
My application is running on weblogic 10.3.3 application server, and for database I am using Oracle database 11g. My problem is that there is table in db, let's say "user.", there is column, let's say "columnA", in this table. This table is updating by some module of application.
What I want if when value of column is "abc.", then I have to show alert to console(IP). {IP can be retrieved from DB as it is configured in DB. this ip will be other linux system other than linux machine where oracle database is installed.} Updating is continuously done on my table from module of application. Please tell me from where should I start?, what should I read. I am not able to understand what should be approach. Any help is much appreciated.
A trigger on the table can call UTL_HTTP to communicate with another machine (eg call a RESTful API).
The architectural questions are :
This will happen PRIOR to the commit so you may get false alerts if a change is rolled back
If you wait for a response, it will slow the system down.
What do you do if you get an non-standard response (eg the other server isn't available)
We develop Win32 application that access to SQL 2005 database through Linq to SQL. The issue is when 2 users access to same record (View and Edit)… User 1 update record (DataContext.SubmitChanges()), User 2 will continue to see old information until he restart application. So, we would like to update context of user 2… The solution that appears right now is to call DataContext.Refresh to sync object with SQL table… We wondering if other solution exist ?
Thank you
I've noticed that Refresh can be really nasty depending on the data you've already grabbed from an entity, another solution is to reset the context you are using to a new instance.
context = new MyDataContext(ConnectionString);
This, at least in the scenarios where I am using it is less overhead and less DB calls.