Using jMeter to read values from DBMS_OUTPUT.PUT_LINE - oracle

what would be the easiest/most efficient way to read the values, that have been put in the buffer already?
I have something like this:
Dbms_Output.Put_Line('a -> 3');
Dbms_Output.Put_Line(a);
And I want to know if I can put anything in my JDBC Sampler, which can read the value of "a" and return it as a response, so I can use it as a parameter in my next request?
I was thinking about Dbms_Output.Get_Line(s), but not sure what should be the syntax and if this will solve my issue.
Thanks in advance!

No, you can execute SQL statements like select or update and call stored procedures and only one statement at a time.
Theoretically you can create a stored procedure like it's described in
How to Fetch Oracle DBMS_OUTPUT from JDBC article but I'm not sure whether it's something you're looking for
More information:
Difference Between SQL and PLSQL
Using JDBC Sampler in JMeter
Samples of PL/SQL in JDBC

Related

Quick method to catch/capture Stored Procedure calls (with parameters) in Oracle?

I need to capture Oracle stored procedures calls (with parameters) to trace an application (which uses JDBC to connect to the DB). I need something like sp_trace_setevent for Rpc:Completed event in MS SQL SERVER.
I do not have access to this application, but have mostly all rights in the database. I would like to stay in PL/SQL (and Oracle SQL Developer 3.2.20).
I have tried:
Oracle SQL Developer UI "Tools"/ "RealTime SQL Monitoring" and "Tools"/ "Sessions" instruments but can't understand how to enabling accumulating information instead of capturing moment snapshot.
exploring v$sql - it seems there are no sp calls.
v$sqlarea differences (Oracle: is there a tool to trace queries, like Profiler for sql server? , mdj3884 reply) - there I am able to find my test call, but without parameters...
Suggestion from Tom's article : http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:767025833873. Particularly, it is looping through v$sqltext_with_newlines, but I can't understand what is a script result. Something more like moment snapshot; isn't it? But then why they call it tracking?
use DBMS_APPLICATION_INFO - as I understand using this I can add custom info to V$SESSION and V$SESSION_LONGOPS - it can be useful for monitoring tasks but I can't imagine how it can be used for accumulating information about sp calls and theirs parameters.
use DBMS_MONITOR for enabling tracing into file. but I can't find option to enable tracing only sp call events, also it requires access to the server files.
DBMS_PROFILER - collects as I understand by default it collects only statistics (min, max time); there should be possibility to add custom information to plsql_profiler_runs but I can't find this table (when DBMS_PROFILER is in place).
What to see next? What I have missed?
P.S. If the only one way is to change SP body (those SP which need to be traced) then what is the quickest and safest way to log sp parameters from sp body in Oracle? It could be logging to custom table, but may be I could choose between generating another types of events (that are not rollbacked, something like SQL Server custom trace events)?
It would be easy to add some custom functionality to do this (see below for most of what is required) or you could use sqltrace or the enterprise manager reports and search through them:
create package p_audit as
type t_param_type is table of varchar2(50) index by binary_integer;
procedure p_audit (p_procedure varchar2, l_param_type t_param_type);
end;
create table audit_table (procedure_name varchar2(50), parameters varchar2(500))
create or replace package body p_audit is
procedure p_audit (p_procedure varchar2, l_param_type t_param_type) is
pragma autonomous_transaction;
begin
insert into audit_table values (p_procedure,l_param_type(1));
commit;
end;
end p_audit;
declare
l_param_type p_audit.t_param_type;
begin
l_param_type(1):='parameter 1';
p_audit.p_audit('test procedure',l_param_type);
end;
I used DBMS_AUDIT trail to determine what kind of procedures/functions/packages used when a client side application executed. I would really recommend you to use it once, it really helps, but problem is that you cannot analise deeper in a package hierarchy, its function/procedure called (calls), but only its usage. If you want to know dependency of the package you can use ALL_DEPENDENCIES. It can be helpful.

Executing an Oracle stored procedure returning a REF CURSOR using SqlAlchemy

I have a stored procedure that I have defined in Oracle. In that procedure I need to return a recordset. To do this, I am using the SYS_REFCURSOR, which works great inside of Oracle (and with cx_Oracle, for that matter). In my application I am using SqlAlchemy scoped sessions, to support multi-threading.
How can I use the scoped session to return the REF CURSOR? The only way I have been able to get this to work is by declaring an out cursor with the cursor that is active in the session and then executing the stored procedure, like below:
sql = """
BEGIN
example('%s', '%s', '%s', :cur);
END;
""" % (cid, show, type)
conn = sa_tool.session.connection()
in_cur = conn._Connection__connection.cursor()
out_cur = conn._Connection__connection.cursor()
in_cur.execute(sql, cur=out_cur)
results = out_cur.fetchall()
Ideally, I would like to avoid using the connection object in this way, and execute the procedure while letting SqlAlchemy manage the cursors. If that is not possible, is there a reason that the fetch would take so long?
Thanks
I saw this question which was not answered and I decided to jump in. First of all, let me just say that for your scenario there is no better option than SYS_REFCURSOR. Of course, you have alternatives.
An Oracle Cursor is a memory area location where an instruction to execute a SQL statement is stored. A Ref cursor is just a pointer to the cursor location. SYS_REFCURSOR is an specific oracle defined typed of ref cursor. So when you return a SYS_REFCURSOR variable to a client, you are returning a pointer towards the memory location where the instruction to execute the SQL resides. Your client can now execute the instruction using the FETCH operation and get the rows. So this is the best possible way to return a result set to the client.
As an alternative, you might use a PIPELINED FUNCTION, but I can assure you that you won't get any better performance. AskTom has a great explanation about this comparison in this article
https://asktom.oracle.com/pls/apex/f?p=100:11:0::::P11_QUESTION_ID:9532870400346178516
Another scenario is whether you want to analyse where the time is consumed, either in the EXECUTE phase or in the FETCH one. If you have a huge time in FETCH, perhaps you might consider transfer the data in another way to the client. If you have a problem in EXECUTION, then you need to make a tuning exercise over your procedure.

How do I debug Oracle dynamic sql in sqlplus?

I have a PL/SQL statement that uses EXECUTE IMMEDIATE to execute a query. However, I'm having difficulty figuring out how to even get the text of the query that's being executed. I can't use dbms_output as the query is greater than 255 characters. Is there any way to make sqlplus echo the string that's passed in to EXECUTE IMMEDIATE?
What version of Oracle are you using? 255 is the default line length for DBMS_OUTPUT.PUT_LINE(). Before 10g we could display 1048 characters in a single call. Since then it is 32K.
Alternatively you should consider using an IDE which supports DBMS_DEBUG. For instance, SQL Developer does so, and it is free from Oracle. Find out more.
You can try to attach a profiler to the database (honestly I have only done that for SqlServer) and run the procedure since the profiler will show any query made to the DB you will be able to pick it up there and do the necessary debugging.
Hope it helps..
How to print large strings N characters at a time.
Modify to suit your needs.
FOR i IN 0..10 LOOP
dbms_output.put_line(substr(my_very_long_string,i*100+1,100));
END LOOP;
You could insert the string into a logging/temporary table and examine it.

How do I log/trace Oracle stored procedure calls with parameter values?

We're looking for a way to log any call to stored procedures in Oracle, and see what parameter values were used for the call.
We're using Oracle 10.2.0.1
We can log SQL statements and see the bound variables, but when we track stored procedures we see bind variables B1, B2, etc. but no values.
We'd like to see the same kind of information we've seen in MS SQL Server Profiler.
Thanks for any help
You could take a look at the DBMS_APPLICATION_INFO package. This allows you to "instrument" your PL/SQL code with whatever information you want - but it does entail adding calls to each procedure to be instrumented.
See also this AskTom thread on using DBMS_APPLICATION_INFO to monitor PL/SQL.
I think you are using the word "log" in a strange manner.
We can log SQL Statements...
Do you really mean to say you can TRACE sql statements with bind variables? Tony's answer is directed to the ability to LOG what you are doing. This is always superior to tracing because only you know what is important to you. Perhaps the execution of your process depends heavily on querying a value from a table. Since that value changes and it's not passed in as a parameter, you could lose that information.
But if you actually LOG what you are doing, you can include that value in your Log table and you'll know not only the variables you passed in but that key value as well.
alter system set events '10046 trace name context forever, level 12'; Is that what you were using?
Yes, I think I should have used the term 'trace'
I'll try to describe what we've done:
Using the enterprise manager (as dbo) we've gone to a session, and started a trace
start trace
Enable wait info, bind info
Run an operation on our application that hits the DB
Finish the trace, run this on the output:
tkprof .prc output2.txt sys=no record=record.txt explain=dbo#DBINST/PW
What we're wanting to see is, "these procedures were called with these parameters" What we're getting is:
Begin dbo.UPKG_PACKAGENAME.PROC(:v0, :v1, :v2 ...); End;
/
Begin dbo.UPKG_PACKAGENAME.PROC2(:v0, :v1, :v2 ...); End;
/
...
So we can trace the procedures that were called, but we don't get the actual parameter values, just the :v0, etc.
My understanding is that what we've done is the same as the alter system statement, but please let us know if that's not the case.
Thanks
are you using 10g
let try with this
exec dbms_monitor.session_trace_enable(session_id=>xxx, serial_num=>xx, waits=>true, binds=>true);
you can get session_id=SID & serial_num=SERIAL# from v$session

Explain Plan for Query in a Stored Procedure

I have a stored procedure that consists of a single select query used to insert into another table based on some minor math that is done to the arguments in the procedure. Can I generate the plan used for this query by referencing the procedure somehow, or do I have to copy and paste the query and create bind variables for the input parameters?
Use SQL Trace and TKPROF. For example, open SQL*Plus, and then issue the following code:-
alter session set tracefile_identifier = 'something-unique'
alter session set sql_trace = true;
alter session set events '10046 trace name context forever, level 8';
select 'right-before-my-sp' from dual;
exec your_stored_procedure
alter session set sql_trace = false;
Once this has been done, go look in your database's UDUMP directory for a TRC file with "something-unique" in the filename. Format this TRC file with TKPROF, and then open the formatted file and search for the string "right-before-my-sp". The SQL command issued by your stored procedure should be shortly after this section, and immediately under that SQL statement will be the plan for the SQL statement.
Edit: For the purposes of full disclosure, I should thank all those who gave me answers on this thread last week that helped me learn how to do this.
From what I understand, this was done on purpose. The idea is that individual queries within the procedure are considered separately by the optimizer, so EXPLAIN PLAN doesn't make sense against a stored proc, which could contain multiple queries/statements.
The current answer is NO, you can't run it against a proc, and you must run it against the individual statements themselves. Tricky when you have variables and calculations, but that's the way it is.
Many tools, such as Toad or SQL Developer, will prompt you for the bind variable values when you execute an explain plan. You would have to do so manually in SQL*Plus or other tools.
You could also turn on SQL tracing and execute the stored procedure, then retrieve the explain plan from the trace file.
Be careful that you do not just retrieve the explain plan for the SELECT statement. The presence of the INSERT clause can change the optimizer goal from first rows to all rows.

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