Tom Kyte

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Updated: 11 hours 58 min ago

Wrong execution plan with domain indexes in or condition

Wed, 2018-06-27 16:46
Hello, I have a very simple query on a table with two columns indexed fulltext. If there are two AND conditions in the where clause, the optimizer uses a correct plan, taking advantage of the two indices. If instead I use the two conditions in OR, ...
Categories: DBA Blogs

why Results cached on one instance cannot be used by another instance

Tue, 2018-06-26 22:26
Want to know why ? Each node in a RAC configuration has a private result cache. Results cached on one instance cannot be used by another instance. However, invalidations work across instances. To handle all synchronization operations between RAC i...
Categories: DBA Blogs

Does PGA have a segment that functions like buffer_cache in SGA

Tue, 2018-06-26 22:26
In direct path read, blocks are read into PGA directly from disk. Where in PGA hold the blocks? Is it work area? How long will PGA hold them? If I have a full table scan and after a while the same session does another full table scan on the same ta...
Categories: DBA Blogs

Listener Log file issue

Tue, 2018-06-26 22:26
hi, please help me to block the particular user entries in the Listener log file.because the size of file was increasing unexceptionally. that user is frequently accessing the db server.i dont want to log the entries for that particular user. ...
Categories: DBA Blogs

How to populate a TABLE type based on an OBJECT TYPE

Tue, 2018-06-26 04:06
Hi All I'm trying to create a table type based on a object type, but when I try to populate it, I get an error. I copied the syntax from several places, and still, it seems i'm doing something wrong. Here's the code <code> CREATE OR REPLACE ...
Categories: DBA Blogs

CONTEXT vs CTXCAT

Tue, 2018-06-26 04:06
Hi Tom, First off all I am newbie to this Oracle Text thing so please bear with me. I am currently evaluating the possibility and interest in changing the use of context indexes to ctxcat indexes in a big database that I use (the text columns ...
Categories: DBA Blogs

Oracle Undocumented Parameter - _PUSH_JOIN_PREDICATE

Tue, 2018-06-26 04:06
Hi, I have a long standing question regarding one of the undocumented parameters of Oracle namely "_push_join_predicate". I personally experienced scenarios where a query (involving multiple big joins) would show up - "Pushed Predicate" in t...
Categories: DBA Blogs

Os Authentication :Eat the cake and have it too

Tue, 2018-06-26 04:06
Hi Tim, Thanx for all your help to the Oracle Community. Is it possible to have a DB user identified externally and also have a DB password so he/she can log both ways Authenticated from os as well as using account name and password FOR...
Categories: DBA Blogs

Version control of pl/sql codes

Tue, 2018-06-26 04:06
Hi, I wanted to know that if there is any way by which we can create versions of the latest copy of pl/sql stored procedures/packages each time we compile. If yes , could you please provide a sample code for the same as currently we do not have...
Categories: DBA Blogs

Backup and Restore records from DB Objects (Table)

Sun, 2018-06-24 15:26
Wanted to check if there is some easy way to create a backup of the tables/schema and use some script that will load back the data from the backup file. I have DBCS access so can run the sh script as well. Please let me know if there is a simpl...
Categories: DBA Blogs

Spot the diffs between two database schemas inside SQL and PL/SQL code

Sun, 2018-06-24 15:26
Hi : I have two Oracle databases (say, PROD and TEST), and in a given schema (present in both DBs) I must assure that the same SQL code (inside views) and/or PL/SQL code (triggers, procs, funcs, packages) exists, disconsidering the non-functional dif...
Categories: DBA Blogs

Making API calls from Oracle database

Sun, 2018-06-24 15:26
In our office, Environment 1: we have an oracle database with Oracle APEX installed. Environment 2: We have a PCI complaint application with some NON-PCI APIs exposed via Kong We want to call the Non-PCI APIs from oracle database and were to...
Categories: DBA Blogs

Cancelling long running queries

Sun, 2018-06-24 15:26
Dear Tom, I'm wondering about how a 'cancel' in Oracle works. For example, I have a long running query and I define a timeout on application level. Once the timeout is reached, the application sends a 'cancel'. What i observed is, that the canc...
Categories: DBA Blogs

materialized view problem while refreshing

Sun, 2018-06-24 15:26
Hi We have have an ORACLE 8.1.7 database on suse linux 7.2 and we have a materialized view with joins and created a primary key constraint on the mview. The refresh mode and refresh type of the created mview is refresh fast on demand. ...
Categories: DBA Blogs

converting TIMESTAMP(6) to TIMESTAMP(0)

Fri, 2018-06-22 08:26
Currently I have a column with datatype TIMESTAMP(6) but now i have a requirement to change it to TIMESTAMP(0). Because we cannot decrease the precision, ORA-30082: datetime/interval column to be modified must be empty to decrease fractional sec...
Categories: DBA Blogs

Mail Restrictions using UTL_SMTP

Fri, 2018-06-22 08:26
Hi Tom, I have a requirement to send email to particular domain mail id?s. But My Mail server is global mail server we can send mail to any mail ids. Is there any options in Oracle to restrict the mail send as global. For example: My mail host is...
Categories: DBA Blogs

DBA_HIST_SQLSTAT and GV$SQL

Wed, 2018-06-20 19:46
Hi, I was trying to create a dashboard comparing historical executions and current executions of multiple SQL statements. I have noticed some differences between stats in GV$SQL and DBA_HIST_SQLSTAT. Could you please help us to understand below po...
Categories: DBA Blogs

Need help in formulating query to fetch previous quote times

Wed, 2018-06-20 19:46
Hi AskTom Team, I have been a big fan of this site since 1999 around the time it came up. First of all, again a big Thank you for your support to Oracle Community since past two decades. I have immensely benefited from this. This time arou...
Categories: DBA Blogs

Partitioned table cleanup

Wed, 2018-06-20 19:46
Hi I have a table that was created for debugging purposes. Every night a jobs kicks off creating a partition of the days inserts on the table based on date. Needless to say have the partitions grown rapidly and have taken up a lot space in the tab...
Categories: DBA Blogs

how to reset a sequence

Wed, 2018-06-20 01:26
Create sequence with no options, and the current value of the sequence is 10. Specify the statements in order to reset the sequence to 8, so that the next value will be generated after 8 is 11. Find out logic.
Categories: DBA Blogs

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