How to check compatible and optimizer version for a Oracle database instance. I want to know if there is any specific command to check the above two versions from SqlPlus. For compatible version, I know following command might do the job:
select * from database_compatible_level;
I want similar command which will tell me optimizer version. Please help.
Run the following commands as sysdba to know the current values set for these parameters.
SQL>conn sys as sysdba
SQL>show parameter OPTIMIZER_FEATURES_ENABLE;
SQL>show parameter COMPATIBLE;
Any database user can check the OPTIMIZER_FEATURES_ENABLE setting by using the EXPLAIN PLAN command:
SQL> explain plan for select * from dual;
Explained.
SQL> select trim(plan_table_output) optimizer_features_enable
2 from table(dbms_xplan.display(format => 'advanced'))
3 where plan_table_output like '%OPTIMIZER_FEATURES_ENABLE%';
OPTIMIZER_FEATURES_ENABLE
--------------------------------------------------------------------------------
OPTIMIZER_FEATURES_ENABLE('19.1.0')
SQL>
Viewing most database parameters require SELECT_CATALOG_ROLE or SELECT ANY DICTIONARY, but luckily this parameter is exposed in the Outline section of the explain plan. The value in the explain plan is technically only for the statement, but as long as you don't change the parameter at the session or statement level, the value from the above query will be inherited from the system parameter.
Related
I'm trying to enable the result cache in Oracle 11g. I have used Enterprise Manager to change the result_cache_max_size and result_cache_max_result values to '1M' and '100' respectively (maybe these aren't optimal settings, but I'm just trying to get it to work!).
After I make these changes I use the following query to see if the changes have really been made:
select * from V$PARAMETER where LOWER("NAME") like '%result_cache%';
I can see that both have been set correctly. However, when I run queries with the result_cache hint, I can see from the Autotrace that the cache isn't being used. If I then run the following query:
SELECT dbms_result_cache.status() FROM dual;
I can see that it's status is 'DISABLED'. Restarting the database just makes the result_cache_max_size parameter go back to 0 (disabled).
How can I enable the result cache?
As you can see from the comments, it's because result cache is an Enterprise Edition feature only and I have Standard Edition.
I'm trying to get the actual value of OPTIMIZER_SECURE_VIEW_MERGING in Toad for Oracle but I don't know how.
Try this:
select *
from v$parameter
where upper(name) = 'OPTIMIZER_SECURE_VIEW_MERGING'
See Oracle doc for details on v$parameter
Your login would need read access to the v$parameter view. FYI, there is no dependency on TOAD for this - just a straight SQL query, can be run from any SQL client.
I am running TOAD 12, and you can also view all the current oracle parameters from the Database/Administer/Oracle Parameters menu item.
I am using Oracle 11g and Toad for Oracle. How can I display execution plan for queries?
In Sql server management studio execution plan can be displayed as graphical format. Is there any functionality/tool like that on Toad for oracle?
CTRL-E
Make sure you've ended the query with a semi-colon (and the query above)
Edit:
You need to set-up the TOAD plan table for use. If you think it's already setup on your DB then you may just need to be granted access. Alternatively in my slightly older version of TOAD it's under:
Database --> Administer --> Server Side Objects Wizard. From here you can create the plan table(s) in a schema that you choose.
You should create the PLAN_TABLE using a script provided by Oracle
which is named UTLXPLAN.SQL and is located in one of the installation folders
on the database server.
Then, you should use the EXPLAIN PLAN statement for generating a plan for a SQL statement, like this:
EXPLAIN PLAN SET STATEMENT_ID = 'your_identifier_for_this_plan'
FOR
... your statement ... ;
Then, you can use either a select from PLAN_TABLE (usually using a hierarchical query) or the DBMS_XPLAN.DISPLAY_PLAN procedure to display the plan.
In the same folder where the UTLXPLAN.SQL file is located, there usually exist
examples of using this procedure.
Also, in SQL*PLUS you can use the SET AUTOTRACE feature.
For TOAD FOR ORACLE
this helped me How do I view the Explain Plan in Oracle Sql developer?, I just write what they did in sql developer and wrote in the toad editor and then execute.
Example
explain plan for select field1, field2 from TABLE_NAME;
SELECT * FROM TABLE(DBMS_XPLAN.DISPLAY);
Check that all queries end with a semicolon, put the cursor on the query you want to analyze and hit CTRL-E.
The first time you could get a popup that asks for the name of the plan table, it suggests TOAD_PLAN_TABLE but it's better to use the standard Oracle table PLAN_TABLE that should be already available. So enter PLAN_TABLE in place of TOAD_PLAN_TABLE (do not specify a schema) and hit OK. You should get a message saying that the object already exists: hit OK again to acknowledge it. Now try CTRL-E again and you'll get the explain plan.
To view/change the currently configured plan table name go to menu "View / Toad Options / Oracle General".
Here is my problem, I wants to create a baseline on our development Dateabase (Oracle 10g), and check into our svn for version control, and after this we will use liquibase to help us manage the incremental database changes.
My problem is how should I create baseline of Oracle 10g? the database now consists of 500+ tables, with large amount of configuration data, and I wants my db baseline to base on a set SQL scripts to check into subversion, rather then check in Oracle dump..
I have try use liquibase generateChangeLog, but it have some performance problem.. can anyone can recommends me any tools that will help me
1. Scan any Oracle Schema
2. Generate a set of SQL Scripts (With Table structures, and Data)..
Thanks in advance
James!
Something like
SELECT DBMS_METADATA.GET_DDL('TABLE',table_name) FROM USER_TABLES;
is a good start. You can tweak it with PL/SQL and UTL_FILE to get it to write each table to a different file. You will probably need to do sequences too (though versioning them is fairly pointless), and maybe triggers/procedures/functions/packages etc.
Don't forget grants.
Have you tried Oracle's free SQLDeveloper tool? It gives you the possibility of exporting DDL and data.
EXPDP with CONTENT=METADATA_ONLY option, then IMPDP with SQLFILE=your_script.sql ?
Nicolas.
More general solution would be to dump DDL sql for selected list of tables, but additionally also other types of objects. This could be done by using all_objects and all_users views.
Example that worked for me:
select dbms_metadata.GET_DDL(u.object_type,u.object_name, u.owner)
from all_objects u
where 1=1
-- filter only selected object types
and u.object_type in ('TABLE', 'INDEX', 'FUNCTION', 'PROCEDURE', 'VIEW',
'TYPE', 'TRIGGER', 'SEQUENCE')
-- don't want system objects, generated, temp, invalid etc.
and u.object_name not like 'SYS_%'
and temporary!='Y'
and generated!='Y'
and status!='INVALID'
and u.object_name not like 'TMP_%'
and u.object_name not like '%$%'
-- if you want to filter only changed from some date/timestamp:
-- and u.last_ddl_time > '2014-04-02'
-- filter by owner
and owner in (
select username from dba_USERS where DEFAULT_TABLESPACE not like 'SYS%'
and username not in ('ORACLE_OCM')
and username not like '%$%'
)
;
I wrote a python script that refreshes db schema in incremental mode based on similar sql:
runs sql with last_ddl_time>=max(last_ddl_time from last refresh)
at the end stores last_ddl_time somewhere in filesystem for next refresh
References:
oracle dbms_metadata.GET_DDL function
oracle all_objects view
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.