What does "rows processed" in Oracle AWR report mean? - oracle

I have an application which uses Oracle Database. I have several sql updates and selects in the application.
I gathered an AWR report on Oracle Database to diagnose some performance charasteristics of my application.
When I analyze the report by checking the "SQL ordered by Executions" statistics, I found out that one of my update query run 8985 times and row number processed by this query is 8,985. But, I have a select query and it run 8,985 times too but row number processed by this select statement is 8936.
My select query is right after the update query so it is expected that both queries' executed time is equal. What I wonder is, why my select query processed less row than its executed time value.
Thanks

conn / as sysdba
SQL> #$ORACLE_HOME/rdbms/admin/awrrpt.sql
Specify the Report Type
AWR reports can be generated in the following formats. Please enter the
name of the format at the prompt. Default value is 'html'.
'html' HTML format (default)
'text' Text format
'active-html' Includes Performance Hub active report

Related

Crystal Reports displays blank (null) values for some fields from an Oracle view

Summary
We have a Crystal Report referencing a single Oracle view. There are no other tables or joins in the report. The view is composed of several selects, joins, and other data transformations (e.g., sum, case, to_date, group by).
Four columns from the view display as blank (null) in the report. These same columns display correctly in Oracle SQL Developer and via a select using the Oracle Data Provider for .NET in a C# application. All other columns display correctly in the report.
In addition the Browse Field option displays no values for the affected fields, but does display options for unaffected fields of the same type. Similarly, if I make an affected field a parameter of the report no options are presented.
We verified that in all cases we are connecting as the same read only user in Crystal Reports, Oracle SQL Developer, and in our Web Application.
Failed Resolution Attempts
We removed and replaced the view and fields in the Crystal Report.
We created a brand new report connecting to the same view.
We created a new view (from the same SQL) to be used in the same report
We verified database via Crystal Reports
We converted implicit date conversion from
score_month = '01-SEP-2017'
to
score_month = TO_DATE('01-SEP-2017', 'dd-MON-yyyy')`
per https://stackoverflow.com/a/37729175/19977
Other Oddities
Exporting the data from the view to a table works, but we want to use a view
We're at a loss as to what the cause of this issue is. Any ideas?
Several edits to the view were required to resolve this issue.
We removed Oracle specific sql per https://stackoverflow.com/a/37729175/19977. Example:
-- replace
TRUNC(sysdate, 'MONTH') AS score_month`
-- with
TO_DATE('01-SEP-2017', 'dd-MON-yyyy')
-- and replace
where score_month = '01-SEP-2017'
-- with
where score_month = TO_DATE('01-SEP-2017', 'dd-MON-yyyy')
Fully qualify all tables and views used in the Oracle view with the schema and table name. Example:
-- replace
FROM table t
-- with
FROM our_schema.table t
It remains unclear why the view would work as intended from Oracle SQL Developer and in application via the Oracle Data Provider for .NET but not from Crystal Reports. Further insight into this issue is welcome.

Evisions Argos - Execute a procedure before the report

We are migrating some reports from Oracle Reports to Evisions Argos. And in Oracle reports, there was a "Before Report" trigger, that would get fired before the actual running of the report query. This allowed us to fill some tables before the query and keep the whole business logic in the report itself. Is it possible to do something like this in Argos? Where could you execute PL/SQL code before running the query for the report? Either at the report or the datablock could work for us.
You can add a dataset to the report and call the procedure(enclosed with begin/end) there.

Oracle - Log the executed query

I have to debug stored procedure which contains a few SQL queries. One of them contains an error. So, I need to execute this SQL query with parameters in other window. I found next query that would help me:
select v.SQL_TEXT
from v$sql v
Unfortunately, this field restricted by 1Kb. In my case I have quite big SQL query and Oracle truncates it. How to log the executed query? I use PL/SQL Developer 10 and Oracle 9i
Unfortunately, this field restricted by 1Kb
If you need the full SQL, then use the SQL_FULLTEXT which is a CLOB datatype instead of SQL_TEXT whcih is limited to first 1000 characters.
From documentation,
Column Datatype Description
------ -------------- ---------------------------------------
SQL_TEXT VARCHAR2(1000) First thousand characters of the SQL
text for the current cursor
SQL_FULLTEXT CLOB Full text for the SQL statement exposed
as a CLOB column. The full text of a SQL
statement can be retrieved using this
column instead of joining with the
V$SQL_TEXT dynamic performance view.
So, use:
SELECT SQL_FULLTEXT FROM v$sql;
By the way, seems like you are actually looking for tracing your session to get the complete details of the procedure and the SQL statements involved. I would suggest to trace the session with level 4 i.e. with the addition of bind variable values.
See How to generate trace file – SQL Trace and TKPROF in Oracle

Crystal Reports Issue turning a string into a number

I'm having one of those throw the computer out the window days.
I am working on a problem involving Crystal Reports (Version 10) and an Oracle Database (11g).
I am taking a view from the database that returns a string (varcahr2(50)) which is actually a number, when a basic SELECT * query is run on this view I get the number back in the format 000000000000100.00.
When this view is then used in Crystal Reports I can view the field data, but I can't sum the data as it is not a number.
I began, by attempting to using ToNumber on the field, to which Crystal's response was that the string was not numeric text. Ok fair enough, I went back to the view and ran TO_NUMBER, when this was then used in crystal it did not return any results. I also attempted to run TO_CHAR on the view so that I could hopefully import the field as text and then perform a ToNumber, yet the same as with the TO_NUMBER no records were displayed.
I've started new reports, I've started new views. No avail.
This seems to have something to do with how I am retrieving the data for the view.
In simplistic terms I'm pulling data from a table looking at two fields a Foreign Key and a Value field.
SELECT PRIMARY_KEY,
NVL(MAX(DECODE(FOREIGN_KEY, FOREIGN_KEY_OF_VALUE_I_NEED, VALUE_FIELD)), 0)
FROM MY_TABLE
GROUP BY PRIMARY_KEY
When I attempted to put modify the result using TO_NUMBER or TO_CHAR I have used it around the VALUE_FIELD itself and the entire expression, wither way works when the run in a SQL statement. However any TO_NUMBER or TO_CHAR modification to the statement returns no results in Crystal Reports when the view is used.
This whole problem smacks of something that is a tick box or equivalent that I have overlooked.
Any suggestions of how to solve this issue or where I could go to look for an answer would be greatly appreciated.
I ran this query in SQL Developer:
SELECT xxx, to_number(xxx) yyy
FROM (
SELECT '000000000000100.00' XXX FROM DUAL
)
Which resulted in:
XXX YYY
000000000000100.00 100
If your field is truly numeric, you could create a SQL Expression field to do the conversion:
-- {%NUMBER_FIELD}
TO_NUMBER(TABLE.VALUE_FIELD)
This turned out to be an issue with how Crystal Reports deals with queries from a database. All I needed to do was contain my SQL statement within another Select Statement and on this instance of the column apply the TO_NUMBER so that Crystal Reports would recognize the column values as numbers.
Hopefully this helps someone out, as this was a terrible waste of an afternoon.

Oracle Execution Plan

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".

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